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HomeMy WebLinkAbout8A - Variance Hearing Crouse CITY COUNCIL AGENDA REPORT MEETING DATE: AGENDA #: PREPARED BY: REVIEWED BY: AGENDA ITEM: JANUARY 22, 2002 8A STEVE HORSMAN, ZONING ADMINISTRATOR JANE KANSIER, PLANNING COORDINATOR PUBLIC HEARING TO CONSIDER AN APPEAL OF THE PLANNING COMMISSION'S DENIAL OF A VARIANCE TO THE LAKE SHORE SETBACK ON THE PROPERTY LOCATED AT 15507 CALMUT AVENUE History: On February 23, 2001, the Planning Department received a variance application from Mr. D. Mark Crouse (applicant/owner) to allow a deck to be located 4' from the Ordinary High Water Elevation on the property located at 15507 Calmut Avenue. The deck was constructed in the year 2000 without a required building permit. Upon processing this application staff determined a second variance was required to permit the impervious surface coverage area to exceed 30 percent. A building permit for the house on this lot was issued in 1995. A condition of approval of the permit stipulated the impervious surface area was not to exceed 30 percent. It should be noted most of the additional impervious surface area, such as the driveway and patio, were added after the completion of the existing house. The variance requested would have permitted an impervious surface of 57.5% on this lot. On June 25, 2001, the Planning Commission denied the deck setback variance, and on June 29, 2001, the applicant appealed the Planning Commissions denial of the variance. On August 20, 2001, the City Council upheld the decision of the Planning Commission to deny the variance to permit a 4- foot deck structure setback from the OHWM. The subject lot has a total area of7,689 square feet and allows for 2,307 square feet of impervious surface to equal the 30% coverage area. The Planning Commission conducted public hearings on this item on June 25, 2001, on July 23, 2001, and on September 10, 2001. After review of the applicant's request with respect to the variance hardship criteria, the Planning Commission directed staff to draft a resolution approving a variance to allow an impervious surface coverage area of 36 percent. On September 24, 2001, the Planning Commission reconsidered their earlier action. The Commission determined a 36% impervious surface variance would not complete the driveway to the existing garage. The Commission L:\O 1 files\O 1 appeal\O 1-099\CrsAplccrpt. DOC 1 16200 Eagle Creek Ave. S.E., Prior Lake, Minnesota 55372-1714 / Ph. (952) 447-4230 / Fax (952) 447-4245 AN EQUAL OPPORTUNITY EMPLOYER therefore approved a 38% impervious surface and directed staff to prepare a resolution to that effect. This variance allowed the applicant to keep a portion of an existing driveway to access his 3-stall garage, while removing the additional parking and rear yard patio areas to accomplish the 38% coverage area. (See Attachments - Certificate of Survey Dated 10/22/01; Proposed Driveway Dimensions; and the Minutes of the September 24, 2001, Planning Commission meeting). The applicant did not appeal the Planning Commission's decision. On October 26, 2001, the Planning Department received a new variance application from Ms. Allison Gontarek, Huemoeller & Bates Attorneys At Law, representing Mr. D. Mark Crouse. This variance request was for an increased impervious surface coverage area of 46.4% rather than the approved 38% in order to retain the existing patio area on the lakeside of the home. The applicant submitted an engineer's report on the need for the patio area to provide soil stabilization around the structures foundation (Attachment - Applicants Hardship Narrative). The subject lot has a total area of 7,689 square feet to the 904' elevation, and allows for 2,307 square feet of impervious surface to equal the 30% coverage area. The area for the house and garage totals 2,152 square feet. The area for the proposed driveway amounts to 792 square feet, and plus 84 square feet to keep the existing front and sideyard steps totals 3,028 square feet or 39.4% impervious area. The lakeside yard patio area of 539 square feet will add 7% to the previously approved impervious surface coverage area of 38%. The total requested impervious surface coverage area equals 3,567 square feet or 46.4% of the total lot area (Attachment - Impervious Surface Worksheet). The applicant proposed a 46.4% impervious surface coverage area to permit the existing patio area to remain due to the need for a "cap" over the fill area around the home's foundation for soil stabilization, as recommended by the engineering firm Professional Engineering Consultants, Inc. (Attachment- Applicants Engineers Letter). The applicant also proposed removing 372 square feet of concrete by modifying the existing 4-foot concrete sidewalks to a maximum width of3' as permitted under the Zoning Ordinance. Sidewalks less than 3' wide are not considered impervious surface by definition. In addition, the applicant proposed removing approximately 186 square feet of existing driveway area in the public right-of-way, and 570 square feet of parking area along the garage on the subject lot. The City Engineering Department reviewed this request, including the engineer's letter ofrecommendation to allow the applicant to keep the existing patio for soil stability. The Engineering Department noted the L:\Ol files\O 1 appeal\O 1-099\CrsAplccrpt.DOC 2 The subject property is a nonconforming platted lot of record, but was developed by the current ownership, which did not meet the conditions spelled out in the building permit for the principal structure, which included a maximum 30% impervious surface coverage area. However, in order to construct a driveway for the approved 3-stall garage, the Planning Commission granted a 38% impervious surface coverage area. The request for a 46.4% coverage area for the patio area, while recommended by the applicant's engineer, has not been supported with calculations by the engineer. In addition, the City Engineering Department has suggested an alternative solution to the problem. 2. Conditions applying to the structure or land in question are peculiar to the property or immediately adjoining property, and do not apply, generally, to other land or structures in the Use District in which the land is located. The existing conditions of the lot area and dimensions are peculiar to the property, and generally do not apply to most other lots within the Shoreland District. However, when all required conditions are applied, the approved variance for a 38% impervious surface area allows for the driveway. 3. The granting ofthe proposed Variance is necessary for the preservation and enjoyment of a substantial property right of the owner. The approved legal building site precluded the need for the additional variance requests. The owner created the hardship when he decided on the building dimensions and location of the structure, as well as the excessive paving of the subject lot. The Planning Commission previously determined the need for some variance to impervious surface; however, the Commission determined a 38% coverage allowed the applicant reasonable use of the property. 4. The granting of the proposed Variance will not impair an adequate supply of light and air to the adjacent property, unreasonably increase the congestion in the public streets, increase the danger of fire, or endanger the public safety. The granting of the requested variances will not impair light and air to adjacent properties or increase congestion, danger of fire or endanger public safety. 5. The granting of the Variance will not unreasonably impact on the character and development of the neighborhood, unreasonably diminish or impair established property values in the surrounding area, or in any other way impair the health safety, and comfort of the area. L:\Ol files\Ol appeal\O 1-099\CrsAplccrpt.DOC 4 absence of calculations in the letter to support the recommendation for the cap. The Engineering Department suggests there are alternative methods to stabilize the soils and retaining wall, which would eliminate the patio cap and the impervious surface coverage area (Attachment - City Engineering Dept. Memo). The Department of Natural Resources submitted comments on the original variance request dated 3/21/01. In essence, their main concern is the existing impervious surface coverage area of approximately 60%, which poses a problem regarding storm water runoff and lake water quality. The DNR is not supportive of issuing an after-the-fact variance, and recommends bringing the impervious coverage area into compliance which is 30% or less. In addition, he DNR is not convinced by the engineer's letter of recommendation, and suggested the City Engineer provide an independent review. However, should it be determined the patio cap is necessary for structural reasons, perhaps other non-essential hard surfaces can be eliminated in their place. Current Circumstances: On December 10,2001, the Planning Commission conducted a public hearing. After reviewing staffs report, and accepting comments from the applicant's representative, the Commission determined the request did not meet eight of the required nine hardship criteria for approval and denied the variance (See Attachment draft Planning Commission Minutes from December 10, 2001). On December 11, 2001, counsel for the applicant submitted a notice of appeal of the action by the Planning Commission denying Mr. Crouse's variance application for a 46.4% impervious surface coverage area. A follow-up inspection of the subject property has been conducted. The deck and impervious surface area remain, as documented on the certificate of survey. Staff shall enforce all of the required conditions for compliance by requiring the property owner to remove the deck and excessive impervious surface area on the subject property upon a final decision by the City Council. Issues: Variance requests must be evaluated based on the hardship criteria as listed in the City Ordinance Subsection 1108.406: Issuance. These criteria and the suggested findings are discussed below. VARIANCE HARDSHIP STANDARDS 1. Where by reason of narrowness, shallowness, or shape of a lot, or where by reason of exceptional topographical or water conditions or other extraordinary and exceptional conditions of such lot, the strict application of the terms of this Ordinance would result in peculiar and practical difficulties or exceptional or undue hardship upon the owner of such lot in developing or using such lot in a manner customary and legally permissible within the Use District in which said lot is located. L:\O 1 files\OlappeaJ\Ol-099\CrsAplccrpt.DOC 3 RECOMMENDED MOTION: REVIEWED BY: 1. Adopt Resolution 02-XX upholding the decision of the Planning Commission to deny this variance request. 2. Overturn the decision of the Planning Commission and direct staff to prepare a resolution with findings of fact for approval of the variance. 3. Defer action on the appeal at this time and continue the agenda item for specific purpose. The staff recommends Alternative #1. L:\O 1 files\O 1 appeal\O 1-099\CrsAplccrpt.DOC 6 The granting of the variance for increased impervious surface area will adversely affect the above stated values by reducing the infiltration/buffer area, which helps to remove the pollutants and increase the potential for shoreland erosion with additional upland water runoff into Prior Lake and thereby affecting the adjacent properties. 6. The granting of the proposed Variance will not be contrary to the intent of this Ordinance and the Comprehensive Plan. The granting of the variance is contrary to the intent of the Ordinance and the Comprehensive Plan by allowing excessive impervious surface conditions than were originally approved by a building permit (30%), and increased by Variance Resolution to 38%. 7. The granting ofthe Variance will not merely serve as a convenience to the applicant but is necessary to alleviate a demonstrable undue hardship or difficulty. The granting of the variance requests appears to serve as a convenience to the applicant, since other means are available to provide soil stability around the structure. 8. The hardship results from the application of the provisions of this Ordinance to the affected property and does not result from actions ofthe owners of the property. The hardship results from the actions of the property owner when he constructed the dwelling in 1995, and subsequently added the deck and paved areas without permits. 9. Increased development or construction costs or economic hardship alone shall not be grounds for granting a Variance. Financial considerations alone shall not be grounds for granting this variance request. The property owner created the need for these variance requests by not following the approved conditions for the original building permit. Conclusion: The staff recommends the City Council uphold the decision of the Planning Commission to deny the applicant's variance request for a 46.4% impervious surface area because the request does not meet eight of the required nine hardship criteria. The Planning Commission approved a 38% impervious surface area variance to allow the applicant to keep the existing 3-car driveway. In addition, the City Engineering Department suggested another option for shoring up the retaining wall and stabilizing the soils around the foundation that would not result in additional impervious surface area or the need for the patio cap area. ALTERNATIVES: The Council has the following alternatives: L:\O 1 files\O 1 appeal\O 1-099\CrsAplccrpt.DOC 5 RESOLUTION 02. RESOLUTION OF THE PRIOR LAKE CITY COUNCIL UPHOLDING A DECISION OF THE PLANNING COMMISSION TO DENY A 16.4% VARIANCE TO PERMIT A 46.4% IMPERVIOUS SURFACE COVERAGE AREA OF THE TOTAL LOT AREA ABOVE THE 904' ORDINARY HIGH WATER MARK ON THE PROPERTY LOCATED AT 15507 CALMUT AVENUE MOTION BY: SECOND BY: WHEREAS, on January 22, 2002, the Prior Lake City Council considered an appeal by Mr. D. Mark Crouse of the Planning Commission's denial of a request for a 16.4% variance to penn it a 46.4% impervious surface coverage area of the total lot area above the 904' Ordinary High Water Mark (OHWM) rather than the required maximum 30% coverage area, for the property legally described as follows: Legal Description: Lot 9, and that part of lot 10, "North Grainwood", and that part of Government Lot 5, Section 25, Township 115, Range 22, Scott County, Minnesota described as follows: Commencing at the northwest comer of said Lots 10 and 9 and also 8, a distance of 165.00 feet to the actual point of beginning of the land to be described; thence westerly along the north line of said plat to the easterly right-of-way line of the Chicago, Milwaukee, S1. Paul and Pacific Railroad; thence northerly along said easterly right-of-way line to its intersection with the westerly extension of the southerly line of the northerly 45.00 feet (as measured at right angles to the northerly line) of said Lot 10; thence easterly along said southerly line to the shoreline of Prior Lake, thence southerly along said shoreline to the south line of said Lot 9; thence westerly along said south line of said Lot 9, to the southwest corner thereof; thence southerly along the westerly line of said Lot 8, to the actual point of beginning; and WHEREAS, the City Council finds that the requested variance does not meet the standards for granting variances set forth in Section 1108.400 of the City Code, and that the appellant has not set forth adequate reasons for overturning the decision of the Planning Commission; and WHEREAS, the City Council has detennined that the Planning Commission's decision denying the requested variances should be upheld, and said variances should be denied. NOW THEREFORE, BE IT RESOLVED BY THE CITY COUNCIL OF PRIOR LAKE: 1) The above recitals are incorporated as if fully set forth herein. 2) The City Council makes the following findings: a. Mr. D. Mark Crouse applied for a variance from Section 1104.306 of the City Code in order to pennit a 46.4% impervious surface coverage area of the total lot area above the 904' OHWM rather than the required minimum 30% coverage area as shown in Attachment 1 on property located in the R-1 (Low Density Residential) and SO (Shoreland) Districts at the following location, to wit; 1:\01 files\O 1 appeal\O 1-099\ccres.doc Page 1 16200 Eagle Creek Ave. S.E., Prior Lake, Minnesota 55372-1714 / Ph. (952) 447-4230 / Fax (952) 447-4245 AN EQUAL OPPORTUNITY EMPLOYER 15507 Calmut Avenue NE, Prior Lake MNJ legally described as Lot 9, and that part of lot 10J "North Grainwood", and that part of Govemment Lot 5, Section 25J Township 115, Range 22, Scott CountYJ Minnesota described as follows: Commencing at the northwest comer of said Lots 10 and 9 and also 8J a distance of 165.00 feet to the actual point of beginning of the land to be described; thence westerly along the north line of said plat to the easterly right-of-way line of the ChicagoJ Milwaukee, St. Paul and Pacific Railroad; thence northerly along said easterly right-of-way line to its intersection with the westerly extension of the southerly line of the northerly 45.00 feet (as measured at right angles to the northerly line) of said Lot 10; thence easterly along said southerly line to the shoreline of Prior LakeJ thence southerly along said shoreline to the south line of said Lot 9; thence westerly along said south line of said Lot 9, to the southwest corner thereof; thence southerly along the westerly line of said Lot 8, to the actual point of beginning; b. The Planning Commission reviewed the application for variance as contained in Case File #01-093, and held a hearing thereon December 10,2002. c. The Planning Commission concluded the variance request did not meet the hardship criteria and denied the request. d. Mr. D. Mark Crouse appealed the decision of the Planning Commission in accordance with Section 1109.400 of the City Code on December 11 J 2001. e. The City Council reviewed the appeal of the Planning Commission's decision, and the information contained in Case File #01-093 and Case File #01-099, and held a hearing thereon on January 22,2002. f. The City Council has considered the effect of the proposed variances upon the health, safety, and welfare of the community, the existing and anticipated traffic conditions, light and air, danger of fire, risk to the public safetYJ the effect on property values in the surrounding area and the effect of the proposed variances on the Comprehensive Plan. The additional impervious surface reduces the infiltration/buffer area, which helps to remove pollutants from the surface water and increases potential for shoreland erosion due to additional runoff. g. The City Council has determined the request does not meet eight of nine hardship criteria. There are not unique circumstances or conditions regarding the property. Any hardship was caused by the actions of the applicant through the design and placement of the proposed structures. There are no unique characteristics to the property that would constitute a hardship. h. The denial of the requested variances does not constitute a hardship with respect to literal enforcement of the ordinance, as there exists reasonable use of the property without the variances. There are other alternatives to providing soil stability around the structureJ which do not increase the impervious surface. 3) The contents of Planning Case File #01-093 and Planning Case File #01-099 are hereby entered into and made a part of the public record and the record of the decision for this case. 4) Based upon the Findings set forth aboveJ the City Council hereby upholds the decision of the Planning Commission denying a variance to permit a 46.4% impervious surface coverage area of the total lot area above the 904' OHWM rather than the required minimum 30% for applicant D. Mark Crouse. 1 :\0 1 files\O 1 appeaJ\O 1-099\ccres.doc Page 2 Passed and adopted this 22nd day of January, 2002. Haugen Hauaen Petersen Petersen Ericson Ericson Gundlach Gundlach Zieska Zieska YES NO {Seal} City Manager 1:\01 files\O 1 appeal\O 1-099\ccres.doc Page 3 ATTACHMENT - CERTIFICATE OF SURVEY 01' \0 of \,; c.Ofl14(.fI 14'1l o~ ,0 of I. A .~~ . <i>\' "Oe ~'fo.'.. \0 ...~'. .\,eu ~e( ~O\ 06' ". ~ 1<' <;0; \1." \. ~o' e,e ,.,. r-c.~ ,,'!>'"" ~ C,oO\~ \. ~O-('" ~e1<' ~o tl\e ~ ~ ~ ~O'tt:", Of Co~C e..~E~E,,^tl.\~ 'to ~ ... o -:::. \ \ ,-- - .- \ \ \ " \ "'IJ '~ 578024'0 \ ~ (J\ \0 _ \0. ~ \ ~b to '0 ~ -t9. -S u.l \'0 00 z ~\ .. Ctl.6\~ ~ ~ o J: s: m z -I I " :D o ." o tJ) m C C :D ;:: m ~ =-< c - s: m z tJ) - o z tJ) Lot siZe 7689 36% impervious House Driveway that allows access to 3rd stall 2768 (2152) 616 792 176 (2%) \ ATTMHUENT - 9/24/01 PC MINUTES MOTION BY STAMSON, SECOND BY ATWOOD, TO ADOPT RESOLUTION 01- 015PC AS PRESENTED BY STAFF. Vote taken indicated ayes by all. MOTION CARRIED. B. Case File #01-017 Mark Crouse Variance Resolution. Zoning Administrator Steve Horsman presented Resolution 01-015PC as directed by the Planning Commission at the September 10, 2001 meeting. Stamson clarified the variance requiring a paved driveway. The concern was the applicant would leave the patio and return to a dirt driveway. We want to avoid that situation. Horsman responded the driveway ordinance regulates a Class 5 action. Allison Gontarek, representing the applicant, asked to be recognized. Chairman V onhof stated the public hearing was closed. MOTION BY STAMSON, SECOND BY LEMKE, RECOMMENDING CITY COUNCIL TO ADOPT RESOLUTION 01-11PC. Discussion: Criego said he did not vote for this the last time based on the 36% impervious surface. Although the Commission felt the property should have a driveway and a reduced sidewalk. The applicant at the time was not prepared to reduce the impervious surface as much as the Commission wanted him to. Questioned the intent to have a driveway with normal curb entrance to a three car garage or only provide concrete to a two car garage. Stamson responded his initial Motion was for staff to determine the impervious surface percentage. The intent was for a three car garage. The issue was to redraft and not delay another two weeks. Horsman responded it would be very difficult to get pavement to the third car garage with the 36% impervious surface. Rye stated the original Motion should be modified to be consistent with the Resolution. MOTION BY STAMSON, SECOND BY ATWOOD, TO RECONSIDER THE VOTE OF SEPTEMBER 10,2001 MEETING PERTAINING TO THIS ISSUE. Vote taken indicated ayes by all. MOTION CARRIED. MOTION BY CRIEGO, SECOND BY STAMSON, APPROVING A VARIANCE TO PERMIT A MAXIMUM OF 38% IMPERVIOUS SURFACE COVERAGE WITH THE CONDITIONS THE APPLICANT SUBMIT TO THE CITY A REVISED SURVEY L:\Ol files\Ol plancomm\Ol pcminutes\MN092401.doc 9 Planning Commission Meeting September 24. 2001 IDENTIFYING THE IMPERVIOUS SURFACE REMAINING AND ALL CONDITIONS OF THE VARIANCE RESOLUTION BE MET INCLUDING THE CONDITION THE APPLICANT REMOVE THE CANOPY AND DOCKAGE NOT INCLUDED IN THE ORIGINAL SURVEY. Horsrnan explained the additional impervious surface and his discussions with the Department of Natural Resources regarding the dockage. Lemke commented this clarifies the Motion from two weeks ago. V onhof stated he believes the variance criteria in this matter are not met and this specific condition has been created by the property owner and will not support the Motion. V ote taken indicated ayes by Criego, Lemke, Stamson and Atwood, nays by V onhof. MOTION CARRIED. 6. New Business: A. Discuss infiltration systems and engineered runoff management. Criego recommended continuing this matter to another meeting. 7. Announcements and Correspondence: 8. Adjournment: The meeting adjourned at 8:11 p.m. Donald Rye Director of Planning Connie Carlson Recording Secretary L:\O 1 files\O 1 plancomm\O 1 pcminutes\MN09240 1.doc 10 HUEMOELLER& BATES ATTORNEYS AT LAW POST OFFICE BOX 67 PRIOR LAKE, MINNESOTA 55372 Telephone: 952.447.2131 Facsimile: 952.447.5628 E-mail: huemoellerbates@aol.com OCT 2 6 2nOl BRYCE D. HUEMOELLER JAMES D. BATES ALUSONJ.GONTAREK OF COUNSEL: CHARLESC.HALBERG October 26, 2001 Prior Lake Planning Commission 16220 Eagle Creek Avenue Prior Lake MN 55372 Via Hand Delivery Re: Request for variance from D. Mark Crouse for increase in impervious surface limitation for 15507 Calmut Avenue Dear Planning Commission Members: The purpose for this letter is to address the hardship criteria and the need for a variance, above the variance for 38% impervious surface granted for a reasonable driveway, on the above property. This is a situation familiar to both staff and the Commission members. We respectfully address the nine hardship criteria and how they apply to Mr. Crouse's property. ! First, Mr. Crouse's property is a narrow, .non-conforming lot, left over from a railroad right of way and other'larger developments. It required two variances to upgrade the existing house built in 1978. Mr. Crouse took the original structure, raised it to meet the current code for elevation requirements and developed it in a manner customary within the neighborhood in which he is located. Second, when Mr. Crouse built his house, the permit issued allowed for a three car garage. At the time of construction, a hard surface driveway was not required by ordinance. It has now been determined and agreed that a reasonable driveway, allowing for access to the third garage stall increases the need for impervious surface to 38% of the lot. Similarly, there is attached a report by an engineering expert explaining the requirement for a "cap" on the area between the house and the adjacent lakeshore. The report states that raising the elevation to meet code required the exterior backfill to be raised and stabilized for structural support and erosion control. The need for additional ~ it (1 :I: 3: m z -I I )> -c -c r- - ~. Z -I en J: )> ~ C en :I: - -c z )> :xl :xl ~ <: m Prior Lake Planning Commission Page 2 October 26. 2001 impervious surface to create a useable driveway and to provide for a cap to ensure stability between the house and the lakeshore are two conditions that arise from the unique shape, size and proximity of the lot to the adjacent lakeshore, and that do not apply, generally, to other land or structures in the Shoreland District. Third, the variance, as requested, is necessary to (1) provide access to a garage that was built under permit, and (2) structurally support the house. Without receiving the requested variance, Mr. Crouse is denied access to his garage and his property is subject to damaging erosion. Fourth, the proposed variance will not impair in any manner either the supply of light or air to the adjacent property, unreasonably increase the congestion in the public streets, increase the danger of fire, or endanger public safety. Fifth, attached to this letter are signed statements made by Mr. Crouse's neighbors as to the benefit his improvements to his property have had on the neighborhood. Sixth, the granting of the variance request will preserve the spirit and intent of the Prior Lake Zoning Ordinances by contravening the undue hardship created by conditions unique to the property due to its shape and size and proximity to the lakeshore. Seventh, it is the expert opinion of a qualified engineer that frost action and erosion must be minimized between the structure and the retaining wall. This i.s not a convenience issue, it is a structural requirement. Eighth, the limitation of impervious surface for lots in the Shoreland District is an essential part of management of the natural resources in and around Prior Lake. However, strict application of the Ordinances creates hardship for unusual and non- conforming lots. Mr. Crouse purchased an undersized platted lot of record. He applied for and was granted a permit to raise and add on to the existing home which created approximately 28% impervious surface over his lot. He raised the house to comply with the current code for old and new elevation. Complying with the elevation requirements of the code created structural problems for the approved structure. Resolving the structural problems adds to the impervious surface problem (that did not exist when the parcel was originally created and improved). Complying with new driveway requirements compounds the impervious surface problem. The hardship results from the application of the old and new ordinances requiring a paved driveway and applying the new elevation requirements to an existing building footprint. Ninth, this has been a very expensive journey for Mr. Crouse. He will have to expend more money once the variance is determined to remove concrete he paid to have Prior Lake Planning Commission Page 3 October 26.2001 installed. Although economic hardship alone is not the basis for approving a variance request, the statute allows consideration of the economics involved. Finally, the issue of whether the need for the variance is attributable to the applicant. We submit that the need for a variance here results from the combined impact of old and new ordinances on this property. Long after the size, shape, location and use of this property were established, a series of new laws on lot sizes, setbacks, paved driveways, minimum elevation, maximum impervious surface, and the like, have made variances a necessity. Complying with one law, requires variances of another. The problem is with the inter-related restrictions, and not with the actions of the applicant to comply with the laws. The need for a variance now arises from a previous lawful action by the applicant - remodeling an existing house with an approved building permit. It does not seem that the lawful actions of a homeowner should provide the basis for the denial of a subsequent variance, where the need for the variance is the result of subsequently adopted laws. To promote the most appropriate and orderly development within the community, the Minnesota statutes authorize zoning ordinances and allow for the Board of Adjustment: To hear requests for variances from the literal provision of the ordinance in instances where their strict enforcement would cause undue hardship because of circumstances unique to the individual property under consideration, and to grant such variances only when it is demonstrated that such actions will be in keeping with the spirit and intent of the ordinance. ... Minn. Stat. g462.357, Subd. 6(2) (emphasis added). Case law states that "[t]he statute is clearly intended to allow cities the flexibility to grant variances where. . . the property owner would like to use the property in a reasonable manner that is prohibited by the ordinance." Rowell v. Board of Adiustment of the City of Moorhead, 446 N.W.2d 917, 922 (Minn. Ct. App. 1989). The "correct standard is whether the proposal was reasonable under the circumstances, and would not be allowed except by granting the variances." Nolan v. City of Eden Prairie, 610 N.W.2d 697, 701 (Minn. Ct. App. 2000). Mr. Crouse should be able to use and protect his property in a reasonable manner. Accessing his garage is reasonable, preventing erosion that could destabilize his foundation is reasonable. The issue of granting a variance after the fact as opposed to consideration of a proposed use is difficult. We respectfully request the Commissioners consider whether it is reasonable to potentially compromise the structural stability of a permitted home based on the timing of the request for a variance. Prior Lake Planning Commission Page 4 October 26.2001 Based on the principles set forth under Minnesota statutes and the Rowell and Nolan decisions, we believe the Planning Commission should find as follows: 1. Literal enforcement of the Prior Lake Zoning Ordinances will result in undue hardship with respect to the Crouse property because it will preclude the preservation and enjoyment of Mr. Crouse's property rights, including a driveway to serve his property as required by ordinance and a concrete slab that is necessary for structural support. 2. The undue hardship results from the circumstances unique to the property because of the shape and size of the lot and its proximity to the lakeshore, as evidenced by the granting of variances in 1978. 3. The undue hardship is caused by the provisions of the Prior Lake Zoning Ordinances and is not the result of the actions of the owner, because the owner's use of the land is reasonable and the literal application of the ordinance would preclude such reasonable use. 4. A variance preserves the spirit and intent of the Prior Lake Zoning Ordinance, produces substantial justice and is not contrary to the public interest, because the reasonable use is consistent in all respects with the existing and proposed land use in the neighborhood, and provides an enhancement to the neighborhood as a whole. We respectfully request that the Planning Commission approve the requested variance to increase the impervious surface limitation on Mr. Crouse's property to 46.5% to allow for a reasonable driveway and the erosion control provided by the cap between the house and lakeshore. Very truly yours, ~:J_ GrrJ~ Allison J. Gontarek W~ AJG:cak Attachments cc: D. Mark Crouse 01' \..o'T \0 , \..INe. 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',.-',\ ",::\ \ ;.,:~\ \ :', .. r " \!'t,\~"':Jt'lUi,) . ~1', ,\0 0' ~~. . .Vjo <ft(' ~~\O ,11':)\'.<.\'\\' , '0". - \ \L"=' ,\,....,. t.\., ,0' '~I>G(. Gt. .11, \006 ~<.\' \H\'\\ ",'t.r:. 9 ~c ~ot\r) i .~~ cf'.y. ~o'~ ~ .'. ~ A~O~" I '7" -7.'-:.:.:~ '-':",,' ..:f- ~ . " .';r." . -~ ~~ ~~ Ul uJ :z:. :. \>I ~ o j: \II l ./., \ ,/ ....\ \a.l ? a: .., io ~ ~ 90). .'-02s-- :',', ~--- ,.....- 70 . '\O"IN '.. "...., \579 26 . 'g.J'" . \ E Of \..0'1' .:. I "'", '!r. S.\..'(\~\..Il'l 'i.\ ~~-;.. \ . \ , 9.... I" \ \ ~ , \ \ .. \; Di.')('i~IF;-'()(.; i\~, PR(l"\-'IDED: Lof <./ and that part of Lot 10. "NORTH GRAINWOOD", and that part of Gover 0101 LUI 5, Section 25. Township /15. Range 22. Scott Countv. Minnesotn descrihed n~' tbllnws: Commencing at the northwest comer of said Lm 10: thence southerly alnng the ATTACHMENT - IMPERVIOUS SURFACE AREA CITY OF PRlOR LAKE Impervious Surface Calculations (To be Submitted with Building Permit Application) For All Properties Located in the Shoreland Distrlct (SD). The Ma.ximum Impervious Surface Coverage Permitted in 30 Percent. Property Address \~"So'" t~~\~u-c-- p....'-S L~~(. N~. Lot Area ~~ ot ~ e..~ qo~.o Sq. Feet x 300/0 = .............. -z. ~o-, ************************************************************************ HOUSE ~ , A IT ACHED GARAGE x = SQ. FEET \\ '-\ '-\ LENGTH WIDTH x = x = \c::a() ~ TOT ALPRlNCIPLE STRUCTURE...................... "'2.\ S'2.... DETACHED BLDGS (Garage/Shed) x X TOTAL DETACHED BUILDfNGS......................~ e.o~~ DRlVEWAYIPAVED AREAS X -c::::.. (Driveway-paved or not) ~~c.. 5k 06 X (SidewalkIParking Areas). ~ X =~ B~ = = TOT AL PAVED .~AS......................................... a,~ CbN,.~~ P A TIOSIPORCHESIDECKS - (O'j)enOecks y," min. opening between boards. with a pervious surface below, are not considered to be impervious) X = t;~q x = x = T OT.~ DECKS ........................................................ 'S'!.c; X X = OTHER = TOT AL OTFIER.... ......................................... ...... ... \ '2..'-0 . J I TOTAL IMPERVIOUS SURFACE UNDER.COVEIU Prepared B~"e.. ~'1l!>-~ company\h.\\~ ~"R"""\:J C ""') t?~. ~t..-( "." " .'p". ... Date ,/ Phone # '-\\l1-'ZS"'1t:> _~~__."..,....,*.,,~,v. ~____. ",' ........, ..__.~ ~.~~..~,_._"_,,_.,.."'.,_~_a_'_.'..... ..". -^.-----.. -~_..""."..",.~.~_.~-~,,_..._'".,,-"_....~"'-_.,~-_._-..-,,,",,-,'~'..'-,-~--, .._".--,-_..__._.~,-~--~.._._._---."_.............-,.~--~..._._~._-~--.-..."-...-.-- PROF. ENGR. CONSULT. 49139265 203 LITTLe C"'N"DA !lOAD SUIT2280 SAINT PAUL MINNESOTA 55117 TEL: 651.490-9266 PAX: 651-490-92.65 Ji. r. ~,1 l; .:\~ '::' 1~ ~, ~()FESSIONAl.. ENGINEERING CONSULTANTS INCORPORJ,TJ-:D October 4, 2001 Mark Crouse 15507 Calmut Ave NE Prior Lake, MN 55372 Subj: Grading Review 15507 Calmut Ave NE Prior Lake, Minnesota - PEC #5091 Dear.' Mr. Crouse: This letter concerns our review of the grading and patio construction for the single fa~ily residential structure at the above referenced address. We 'uriderstand the structure was built wi th a basement floor elevation .lbwer than currently allowed for residential structures on the,lake~hore. Therefore, the wood framed portion of the structure wai rai.ed, four courses of block were added to the perimeter foundation and fill was added inside of the structure to support a lower level floor slab. Now the lower level floor slab complies with current elevation requirements. These alterations required changes to the exterior grading. On the lake side of the structure the grading changes required the following engineering considerations: 1. The exterior grade had to be raised to balance the lateral soil loadings on the taised section of the rear foundation wall. 2. The grade required a cap to prevent surface water infil tration into the backfill region to reduce frost action and provide erosion control. Erosion .control was required between the shoreline and the building'. In addition to the engineering considerations,where the function and maintenance considerations for the construction. There was a 51 iding glass doorway in the lower level and a need to provide maintenance access for the lake side face of the construction. Th~s~ requirements and engineering requirements were accomplished by constructing a near level grade with a retaining wall. The r~taining wall also had a requirement to reduce lateral frost action against the wall. Therefore, the top of the grade had to he capped to minimi~e surface water 'runoff from percolating into the subgrade soils. P.131 ~ :s o ::I: 3: m z -I . J> ." ." r- - ~ Z -I (J) m Z C) - Z m m :%J (J) r- m -I -I m :D PROF. ENGR. CONSULT. 49139265 p.a2 PaS" Two The pa.ved patio a.rea fulfills the cap requirement over the backfill. It minimizes the s~rface water infiltr~tion to reduce frost action in the subgrade soils and it keeps water away from the fO'l.lOdation. It also provides erosion protection for the subgrade. During our observations on October 1, 2001, ",e observed a gap between the foundation wall and the patio slab. This gap ~hould be sealed wi tha flexible joint sealant to prevent dirt and water migration into the gap. The saW joints in the patio also should be sealed with joint sealant. The patio sla.b extends to the outside edge of the reta.ini.ng wa.ll. This construction detail mi.nimi zes water infi1 trat ion bp.hi.nd t.he bacl~ of the retaining wall. 11 ~oU have any questions regarding our review, please contact us at ti51-490,:",9266. Respectfully, 'PirOf~~ss~n~5 .E;ginle ing Consultants, Inc. /' ~ I"\..t ./;/ ~~.tt-"l ~ hn F. Gislason, r., P.E. Profe~aional Engineer JFG/fm cc: Allison Gonta.rek 952-447-5628, Fax PROF. ENGR. CONSULT. 4909265 P.01 2U3 L.ITTI.J:; CANADA ROAD SUITE 2R(J SAINT PAUL MINNllSOTA 55117 T'6I.: 6~1 ~90-9266 "AX: 6.:l1-49().9:1.6S . ' . " ,.: ~Ol'jo;SSlONAL fo;NGlNY.ER.Ji"G CONSULTANTS INCllRI'Ollo\Tl1l) December 6, 2001 Allison Gontareck Fax - 952-447-5628 Subj: Grading Revj.ew 15507 Calmut Ave NE Prior Lake, MN Dear Ms. Gontareck: This letter concerns our review of the grading and patio construction for the single family residential struct.ure at the above referenced address. You furnished us a copy of a memo dated December 4, 2001. from Lani Leichty, Water Resources Coordinator, addressing our recommendations. The memo states no engine~ring calculations had been provided to support our claim that a Gap was required to prev~nt water infiltration. ' Our recommendations on the benefjt of the cap were not determined by calculations. they were based on experience. WRter is detrimental to construction I especially when it free~es. We recommend reduci ng surface water inf:i.l tration adja~ent to construction and in areas where there is an excess a.mO\Jnt of surface water infiltration, we recommend installing a tile sy~tem to drain away water from the construction. Water free~ing adjacent to construction is very detrimenta.l to the construction. Expansive forces from freezing water crack and lift foundations. Water freezing in building materials degrades the desirable features of the building material due to repeated cycles of free~in.g and thawing. The first problem I was taught to address in buildinJ{ construction wa.s "Wha.t are YOll going to do with the wat.er", "How are you going to drain it away", "How are you go ing t.o prevent it. from damaging the construction". Experience has taught us to provide a cap around the construction with sealed joints to minimize surface ~ater infiltration around construction. Respectfully, Professionel Enginee~g Consultants, J::~::~:., P.E. Inc. Memo DATE: December 18, 2001 TO: Steve Horsman, Zoning Administrator cc: Sue McDermott, City Engineer FROM: Lani Leichty, Water Resources Coordinator RE: Variance Request for 15507 Calmut Avenue NE The engineering department has reviewed the variance request for the above mentioned property and has the following comments: 1) One of the land use practice goals in the Comprehensive Lake Management Plan for Upper and Lower Prior Lake (CLMP) is to: Minimize the transport of nutrients, sediment and runoff from city streets and lands which impact the Prior Lake watershed. Action step 5-2a in the CLMP is to: Require a natural upland buffer strip around delineated wetlands and waterbodies for new construction. One way of achieving this is to provide buffer strips around waterbodies. Allowing an impervious surface directly adjacent to the lake does not provide any measure for improving the quality or quantity of stormwater runoff leaving a site through filtering. 2) It is the policy of the Prior Lake-Spring Watershed District to reduce the following actions that impact Prior Lake: 1) activities that degrade runoff quality, 2) activities that increase rate of runoff, and 3) activities that increase the volume of stormwater runoff. Allowing these actions only exacerbates the underlying problems faced by both the City and Watershed District, which are water quality, water volume and public expenditures to improve these problems. 16200 EHgMIB~tlf\varM€mJ2"!€to~ke, Minnesota 55372-1714 / Ph. (952) 447-4230 / Fax (952) 447-4245 AN EQUAL OPPORTUNITY EMPLOYER ~ ~ (1 3: m z -I I o - -I -< m z C) - z m m :XI - Z C) c m ~ . ~ m ~ o 3) The letter dated December 6, 2001, from Professional Engineering Consultants, Inc. provided a solution to the problem of freezing water adjacent to construction. City staff agrees with their recommendation of "installing a tile system to drain away water from the construction." Another option, along with drain tile, is to remove expansive soils in the backfill region and replace them with granular soils. This will reduce the potential of frost action around the building. Installation of gutters, routed away from the building, will also help reduce water ponding adjacent to the structure. Several hundred homes a year are built in Prior Lake. Placing an impervious cap around the perimeter of the structure is not a regular practice by builders. A typical method of dealing with drainage is to install footing drain tile, use granular backfill, install a clay cap over the backfill and Slope the ground away from structure. Summary: Engineering does not support the variance as requested. 2 Al"TACHMENT - DRAFT 12/10/01 PC MINUTES Planning Commission Minutes December 10.2001 Criego: . No matter what this development is, the issue of traffic is going to come up. We have to believe the traffic study as it will not change the seasonal traffic. . If the developer comes back with less townhomes, the same traffic issues are going to come up. . The main issue is that this project does not conform to the Pun criteria. It does not give the community enough for what it is requesting. Atwood: . In reading over the traffic study - there is no way Duluth Avenue can handle that traffic. . One of the concerns of the neighbors is the times of the study do not reflect the true traffic of the neighborhood. Because of the school, there are more buses and parents in the area. . Regarding the street lighting narrative by the developer - The developer said he would mount the lights on the building but did not see it on the plans. . Another question is the additional 11 parking spaces. Blocks 6 and 7 will not conveniently be able to access those spaces. . Kansier said the City requires decorative and adequate lighting. MOTION BY ATWOOD, SECOND BY CRIEGO, TO RECOMMEND DENIAL OF THE REQUEST FOR THE APPROVAL OF A PLANNED UNIT DEVELOPMENT KNOWN AS EAGLEWOOD EAST. Vote taken indicated ayes by all. MOTION CARRIED. DRAFT MOTION BY ATWOOD, SECOND BY CRIEGO, TO RECOMMEND DENIAL OF THE PRELIMINARY PLAT TO BE KNOWN AS EAGLEWOOD EAST. Vote taken indicated ayes by all. MOTION CARRIED. This will go before the City Council on January 7, 2001. A break was called at 8:23 p.m. The meeting reconvened at 8:28 p.m. B. Case #01-093 D. Mark Crouse of 15507 Calmut Avenue, is requesting a variance to exceed the allowable impervious surface coverage area. Zoning Administrator Steve Horsman presented the Planning Report dated December 10, 2001, on file in the office of the City Planner. The Planning Department received a variance application from Ms. Allison Gontarek, Huemoeller & Bates Attorneys At Law, representing Mr. D. Mark Crouse the owner of the property at 15507 Calmut Avenue. The applicant is requesting a 1,260 square foot variance to permit an impervious surface coverage area of3,567 square feet (46.4%) rather than the permitted maximum area of 2,307 square feet (30%). L:\O 1 files\O 1 plancomm\O 1 pcminutes\MN 12100 J.doc 11 Planning Commission Minutes December 10,2001 On October 8, 2001, the Planning Commission granted a variance for an impervious surface coverage area of38% (Resolution Ol-OllPC). This variance allowed the applicant to keep a portion of an existing driveway to access his 3-stall garage, while removing the additional parking and rear yard patio areas to accomplish the 38% coverage area. The applicant has since received an engineer's report on the need for the lakeside patio area to provide soil stabilization around the structure foundation. The City Engineering Department reviewed this request, including the engineer's letter of recommendation to allow the applicant to keep the existing patio (cap) for soil stability. The Department noted the absence of calculations in the letter to support their recommendation for the cap. However, without conducting an analysis of the subject site, the Engineering Department does not support nor dispute the applicants engineer of record. The Department does suggest there are alternative methods to stabilize the soils and retaining wall thereby eliminating the patio cap and the impervious surface coverage area. The Department Of Natural Resources submitted comments for this report. In short, the DNR is not convinced by the engineer's letter of recommendation, and suggested the City Engineer provide an independent review. However, should it be determined the patio cap is necessary for structural reasons, perhaps other non-essential hard su:faces can ~ T eliminated in their place. DR At The staff recommended the Planning Commission deny the applicant's variance request for 46.4% impervious surface area as the request does not meet all ofthe hardship criteria due to existing conditions on the nonconforming lot of record, the approval for a building permit to construct the existing structure with a 30% impervious surface coverage area, and the recently approved 38% impervious variance. In addition, the City Engineering Department suggested another option for shoring up the retaining wall and stabilizing the soils that would not result in additional impervious surface. Stamson questioned the assumption is going from 30% to 38% to finish the driveway. Horsman said the 38% granted was to allow the applicant to have the driveway. What came up after the fact was the letter to allow the patio. Stamson clarified that if the Commission denies this request, the applicant can still have the 3-car driveway but has to remove the patio. Criego questioned if the City Engineer came up with any recommendations. Horsman responded the City Water Resource Coordinator looked at it but did not submit a response in writing but in discussions did recommend improving the existing retaining wall or replace it to stabilize it to do the job it was intended to do and then by p1antings, sod or other vegetation allowing an impervious area should not dis-stabi1ize the soils in that area. L:\O 1 fi1es\O 1 plancomm\O 1 pcminutes\MN 121 00 l.doc 12 Planning Commission Minutes December 10.2001 Comments from the public: Allison Gontarek, representative for D. Mark Crouse, distributed a response generated by the engineer based on the staff report. One of the points in the staff report is that there were no calculations done. According to their engineer it is a water problem in this situation and not a calculation issue, it is more of keeping the structure safe from erosion. Mr. Crouse did go ahead and create the impervious surface without a variance relying on wrong information, however he did not create the hardship or the practical difficulties of this lot. He was permitted and did expand and raise the existing footprint to comply with the elevations requirements. Gontarek spoke to Lani Leichty (Water Resource Coordinator for the City of Prior Lake), who did not have a specific alternative but to possibly use drain tile and correcting the retaining wall. Both ofthe suggestions also have problems. The applicant suggested using alternative management runoff methods. The amount of impervious surface that is going to increase on the patio is not much. Gontarek is not disputing the variance should have been applied for but felt this was a reasonable use. They could not get the patio information for the first variance request. Mr. Crouse will correct the problems but does not want to jeopardize his home. He would like to work with the Planning Commission and come to a reasonable decision. Gontarek also said Lani Leichty felt the Watershed District requirements are becoming more of an issue. The public hearing was closed at 8:43 p.m. Comments from the Commissioners: . DRAfT Atwood: . Not in favor of the request. The request is a gross number to be dealing with. . Supported staffs recommendation to deny. Criego: . Agreed with staffs recommendation. Stamson: . Agreed with staff s recommendation. The intent of the impervious surface regulations is to prevent water runoff from the lake. . This patio was built specifically to run water to the lake. It is direct conflict with the intent of the Ordinance. . There also seems a resistance to remove the concrete and a retaining wall that was not built appropriately, which is another lake water issue. . Other agencies familiar with the property feel there are alternatives to protect the building structure yet not defy the Ordinance or its intent. . It is an economic issue is not a hardship. . Supported rejecting this variance. L:\01fi1es\0Iplancomm\01pcminutes\MNI2100l.doc 13 Planning Commission Minutes December 10,2001 MOTION BY CRIEGO, SECOND BY ATWOOD, TO ADOPT RESOLUTION 01- 025PC DENYING THE APPLICANT'S REQUEST TO PERMIT A 46.4% IMPERVIOUS SURFACE COVERAGE AREA. Vote taken indicated ayes by all. MOTION CARRIED. Horsman stated the applicant has 5 business days to appeal. 6. Old Business: None 7. New Business: None r;.',..~~_.. r y,:,' !AFT l~ <<"Yf:f-' !L;di"w\ .... '." . 8. Announcements and Correspondence: Criego requested a workshop for the Planning Commission. Rye said that was the intent with the new commissioner on board. Stamson stated the City was looking for applications for a new commissioner. Applications are available from Administration before December 18, 2001. 9. Adjournment: The meeting adjourned at 8:46 p.m. Donald Rye Director of Planning Connie Carlson Recording Secretary L:\Ol files\O I plancomm\O 1 pcminutes\MN121 001 ,doc 14 ATTACHMENT - CERTIFICATE OF SURVEY ~ \0 of ~o' ....-r'" \,.\" E. ~O"" r:.o~.-... "", Oif \0 ~'" . ..,\(\~ '0' ~.,.~ \0 ...~'. .~\..~ ~Q ~O\ 06' ~. ooe ~ ..0.' \7.*' \. ~l .'. .... t\t:.~ *,~'-J ~ ~O.~ \. ~O ~.<fP ~O ~ ~ -a, ~ o ~ ,-- - -- \ \ '\ , \ - \6.50 -'14 '~ S -ri/ 24' \ ~ ~ 1.0. '0 ~.\O~. to . ..J . ~ '5 e~ ~ \0 4L. % -u _--=::L _ ~ "- c~e\~ ." ,l . -a .~ ." o en m '0 ;'0 :D <: m ~ =-< c i m z en 6 z en L t " '\ 1 ") ~. \........ · '1 Memo a DATE: December 18, 2001 TO: Steve Horsman, Zoning Administrator cc: Sue McDermott, City Engineer FROM: Lani Leichty, Water Resources Coordinator RE: Variance Request for 15507 Calmut Avenue NE The engineering department has reviewed the variance request for the above mentioned property and has the following comments: 1) One of the land use practice goals in the Comprehensive Lake Management Plan for Upper and Lower Prior Lake (CLMP) is to: Minimize the transport of nutrients, sediment and runoff from city streets and lands which impact the Prior Lake watershed. Action step 5-2a in the CLMP is to: Require a natural upland buffer strip around delineated wetlands and waterbodies for new construction. One way of achieving this is to provide buffer strips around waterbodies. Allowing an impervious surface directly adjacent to the lake does not provide any measure for improving the quality or quantity of stormwater runoff leaving a site through filtering. 2) It is the policy of the Prior Lake-Spring Watershed District to reduce the following actions that impact Prior Lake: 1) activities that degrade runoff quality, 2) activities that increase rate of runoff, and 3) activities that increase the volume of stormwater runoff. Allowing these actions only exacerbates the underlying problems faced by both the City and Watershed District, which are water quality, water volume and public expenditures to improve these problems. ~gMISm!!Jt\Wtr~~o~e, Minnesota 55372-1714 / Ph. (952) 447-4230 / Fax (952) 447-424! AN EQUAL OPPORTUNITY EMPLOYER 3) The letter dated December 6, 2001, from Professional Engineering Consultants, Inc. provided a solution to the problem of. freezing water adjacent to construction. City staff agrees with their recommendation of "installing a tile system to drain away water from the construction." Another option, along with drain tile, is to remove expansive soils in the backfill region and replace them with granular soils. This will reduce the potential of frost action around the building. Installation of gutters, routed away from the building, will also help reduce water ponding adjacent to the structure. Several hundred homes a year are built in Prior Lake. Placing an impervious cap around the perimeter of the structure is not a regular practice by builders. A typical method of dealing with drainage is to install footing drain tile, use granular backfill, install a clay cap over the backfill and slope the ground away from structure. Summary: Engineering does not support the variance as requested. .ATTACHMENT \- IMPERVIOUS SURFACE AREA. . '..~CITY OF PRlORLAKE . ,Impervious ~urface Calculations (To be Submitted with Building Permit Application) For All Properties Located in the Shore land Distrl"ct (SD). The Maximum Impervious Surface Coverage Permitted in 30 Percent PropertyAddress \~~"'1-t'~o..\"""\I~ --" €.~~~ ~~' Lot Area ~~ ct . ~ ~\.u C\~ Sq. Feet x '3.0% = .............. -z. ~o, '****.******************************************************************* HOUSE , ~ ATTACHED GARAGE x .. SQ. FEET \ \ \.\\t , LENGTH WIDTH x .. x .' \CI~ ~ TOTAL 'PRINCIPLE STRUCTURE-.---._-- ~ \';'2.. DETACHED BLDGS ' ' . . ' (OarqelShed) x x . ". . TOTAL DETACBJtD BUILDINGS-~-.~....~ e..N..~ .,. . D~AYfPAVEDAREAS. iX (Driveway-paved or not) ~~ ~ 6 X (SidewalkIParlcing Areas) .' " x -~, -~ . TOTAL P A ~D ~AS......_............................._.. 81<' c...~ &.\~ . , P A TIOSIPORCHES/DECKS (Open Decks 'A" min. opening be~cen 'boards. with a pervioUs surface: below. arc: ROt c:onsidUed to be impervious) x .. ';~q x = x = TOT..U DE (:::KS......-................................................ 'S~~ ." " x X = OTHER = TOT AL O~R.-............................_...................... TOTAL I1"VIPERVlOUS SURFACE UNDafOVER) PreparedB;ll~~ ~ ~...\ ~.. COlnpany~\'4 ~..S~ (' -Q') p.~. '\ ~~( I \'2-'-0' J J -;. ~ . :;0.... "~., Date J Phone # ,",\11-'Z.~it) ".,_.~___...--...-_.,__,____._,N..~."._.,.._.~_.""__.._.-'---~-_._~.---~.._- D. MARK CROUSE VARIANCE APPLICATION FACTS: 1. The work is done 2. Owner is willing to work with City 3. Excellent site to do alternate infiltration demonstration/design ARGUMENTS: 1. Hardship criteria 2. Reasonable use 3. Due Process Violations SOLUTIONS: 1. Brave - set conditions on variance to require alternate infiltration to bring actual impervious surface runoff to <t 30% 2. So-So -leave variance at 38% and lose opportunity to benefit from knowledge to be gained by the use and monitoring of new infiltration technologies ___~_"_"'_"A_"'_'_'.""_"';'___'_'__".'~''''__'''''~..".._~~_~,.."",..._."",,..,,.."..."."."_,~~"_______~"___.__.----------.........'""'~~-_..- PROPOSAL BY D. MARK CROUSE 15507 CALMUT AVENUE NE TO PRIOR LAKE PLANNING COMMISSION September 10, 2001 Based on the application for an increase in impervious surface on the above referenced property, the following is proposed: 1. That approximately 1,000 square feet of concrete be removed at owner's expense; 2. That an infiltration system be designed using alternative infiltration devices or a drainage easement be acquired for drainage rights onto the outlot immediately adjacent to the property or some combination of infiltration system combined with drainage easement be formulated by the owner to meet or exceed the runoff management intent of the impervious surface limitation; 3. That the engineered design be approved by this Commission upon engineering analysis demonstrating that the runoff management plan meets the 30% impervious surface calculation for the above referenced property. City Farmer:Rain Barrels Page 1 of 8 Published by City Farmer, Canada's Office of Urban Agriculture Rain Barrels Michael Levenston Executive Director City Farmer (C) Copyright: City Farmer Food gardens need water and what better way to give plants a drink than with soft, warm, oxygen-fined rainwater straight from the rain barrel. Even just a wee bit saved in a barrel after a storm, then transferred to a watering can, win slake the thirst of a balcony of plants. And you, the recycler, will feel especially good knowing that you are diverting water that would otherwise flow out into the storm sewers. City Farmer has been chosen by Vancouver's City Hall to display and help promote a rain barrel distribution program. City Makes Rain Barrels Available to Save Water City of Vancouver Rain Barrel The City of Vancouver is providing subsidized rain barrels for up to 1,000 residents under a pilot program to conserve water. The Green Barrel pilot program will offer Vancouver residents (City of Vancouver - only) a 7S-gallon plastic rain barrel for $S8.06 including taxes. This is half the regular cost. .Cllr of Vancouver rain barrel now available to people outside Vancouver (not subsidized). (February 2001). Residents can use the specially-designed barrels to collect rain water from downspouts for lawn and garden irrigation. http://www.cityfarmer .org/rainbarreI72.html 09/08/2001 City Farmer:Rain Barrels Page 2 of 8 Lawn and garden watering make up almost 40 per cent of total household water use during the summer. It's expected that each barrel will save about 1,300 gallons of water during the peak summer months when demand for water is high and precipitation is low. The barrels are easy to install. They come with outlets for both watering cans and hoses, and are designed with child-proof openings. Yan~.Q!!yer Rainbarrel Vancouver residents can call the City's Water Conservation Hotline at 873-7350 for information on obtaining a barrel. Residents can also visit City Farmer, at the City of Vancouver's Compost Demonstration Garden, at 2150 Maple Street to see the rain barrels in use. Further information: Jeff Smyth jeff smythCWcity.vancouver.bc.ca Waterworks Design (604) 871-6144 Rainbarrel Links on the Internet: Thanks to Lisa Taylor of Seattle Tilth Association for many of these links. Rain Barr~l Information and Sources for the Pacific NOlthwest The Water & Land Division of the King County Department of Natural Resources Rainwater Harvesting information City of Seattle Water Conservation information Texas Rain Harvesting Garden Waters aver "The Garden Watersaver is an automatic rain water collection system that has advantages over other rain water collecting systems. " Spruce Creek Rainsaver Rain Barrels m?de by Arbour Coll~j~t Rainwater for Gardening, Aquariums. and Pets Green Culhlre's Water Savers . http://www.cityfarmer.org/rainbarrel72.html 09/08/2001 . City Farmer:Rain Barrels Page 3 of8 Dan Borba's Rainbarrels Approved Rainbarrel Suppliers Great American ~tn Barrels B!:!in Barrels Rain Pail ReaL Goods Rain Barrel (Type in "Rain") Portland Rainbarrel Rainwater to Drinking Water "The biggest issue in collecting rainwater is keeping it free of muck such as leaves, bird droppings and dead animals, and avoiding contamination with pollutants like heavy metals and dust." From the Sustainable House "In 1996, a Sydney family set out to renovate their 100 year old terrace house in the inner- city suburb of Chippendale. With a bit of vision, some common sense, and a lot of tenacity, they built what most of us would think impossible... a house in the middle of Australia's biggest city that produces its own power and water, and reuses its sewage on site." CMHC's Healthy House in Toronto Melbourne Water Autonomous House The Cam:gus Center for.A:gpropriate Technology Oasis Design Ecologi~ill Design. Consulting Water, W astewat~r & Solar Systems Edible Landsca12ing. Greywater Books City of Etobicoke Utility Engineering 399 The West Mall Etobicoke, Ontario, M9C 2Y2 Phone: (416) 394-8379 City of Toronto . http:j jwww.cityfarmer.orgjrainbarreI72.html 09/08/2001 'City Farmer: Rain Barrels Page 40f8 Public Works 100 Queen St. West, 14th Floor Toronto, Ontario, M5H 2N2 Phone: (416) 392-7660 Fax: (416) 392-7874 Downspout Disconnection Program (Phone: (416) 392-1807 The Rain Saver from Water Conservation Technology P.O. Box 121, Sydenham, Ontario KoH 2To Canada The 'International Rainwater Catchment Systems Association (IRCSA) The IRCSA is a new association aiming to link those with an interest in the direct collection of rainwater and its storage for domestic and agricultural supply. The seeds for the establishment of the Association were first sown when the first International Rainwater Cistern Systems Conference was convened in Hawaii in June 1982 by Prof. Fok. Subsequent International Conferences have followed on a two-yearly basis and were held in the US Virgin Islands (1984), Thailand (1987), Philippines (1989), Taiwan (1991), Kenya (1993) and China (1995). . "Whilst rainwater catchment systems have long been utilised in some parts of the Caribbean, Middle East and Australia, in other places its potential has only recently been realised. During the last decade, Thailand and Kenya, for example, have led their respective continents . http:j jwww.cityfarmer.orgjrainbarrel72.html 09/08/2001 City Farmer: Rain Barrels Page 5 of 8 in demonstrating the enormous potential of this technology. In Thailand more than 10 million two thousand litre ferrocement roof catchment tanks have been constructed since 1985 for domestic water supply, while in Kenya the construction oflarge (10 to 100m3) ferrocement tanks has gained popularity in many regions with thousands being built at schools, clinics and private homes. "Utilisation of rainwater catchment systems has also been spreading in other parts of Asia (e.g. Nepal, Bangladesh, India and the Philippines) as well as in Africa (e.g. Botswana, Mali and Tanzania). In industrialised countries too interest in rainwater collection is growing as demonstrated by recent developments in Australia, Hawaii and Singapore. Japan has traditionally used rainwater catchment systems and is currently making adjustments to meet the requirements of urban environments." IRCSA Membership Account: cj 0 International Water Resources Association 1101 West Peabody Drive Urbana IL 61801-4723 USA More Information: Mr. John E. Gould Secretary-General (IRCSA) University of Botswana P jBag 0022 Gaborone, Botswana Further Reading: Raindrop (Newsletter of the IRCSA) Tokyo International Rainwater Utilization Conference Rainwater & You "100 Ways to Use Rainwater" by Group Raindrops Organizing Committee for the Tokyo International Rainwater Utilization Conference Sumida City Office Building 1-23-20 Azumabashi, Sumida City Tokyo 130, Japan 1995, 176 pages -. .if - "L'r--.. ..J- : ) J v' ,.,l~, r _\.-'" I . ~ ,- "It is.estimated that 60% of the world population will concentrate into urban areas by the middle of the 21st century. ... Population in Asia, Mrica and Latin America will continue to concentrate into large cities and, as a result, those cities will . http://www.cityfarmer.org/rainbarrel72.html 09j08j2001 . City Farmer:Rain Barrels Page 6 of 8 confront the problem "Urban Droughts and Urban Floods". ... A new rainwater culture is required in which cities can live more harmoniously with rain." (from the forward by Makoto Murase, Conference Secretary-General) Also available from the above office: Excerpts of Questions & Answers Tokyo International Rainwater Utilization Conference March 1995, 41 pages The rain falling on the roof of the Sumida City Office, an 18-storey building completed in 1990, is collected in an underground 1000 m3 tank. The drainage from the bathrooms and restaurants in the building as well as the rainwater, is sterilized and used for flushing toilets. According to data from 1993, the amount of water used for flushing toilets for that year was about 13,600m3. 7000m3 of that was rainwater, and recycled drainage accounted for 4000m3. This means that within the City Office alone, 11,000m3 of water were saved during that one year. This amount is equivalent to the amount of water needed to fill approximately 55,000 family bathtubs (200 liters) . Water-Saving Devices Compiled by Lone Hansen, Andrew Giles BSRIA (The Building Services Research and Information Assoc. Bracknell, Berkshire, UK One of six reports in a series on Environmentally Friendly Systems and Products Published in October 1997, 49 pages This series of reports was funded by the Department of Trade and Industry and a group of industrial sponsors. Market report now available from BSRIA, priced E.250. Contact Rachel Slater or Peter Cooke Tel: +44 1344426511, Fax: +44 1344487575 f~tel'Co(W bsria.co. uk The Water Saving Devices report reviews the market for these products world-wide, assesses their market potential in the UK and examines what can be done to increase the uptake of this technology. Those water saving devices analysed in the report include: . Rain water recycling products/systems . Grey water recycling products/systems . Waterless urinals "There are two categories of waste water: grey and black water. Grey water is all http://www.cityfarmer .org/rainbarreI72.html 09/08/2001 . City Farmer:Rain Barrels Page 7 of 8 waste water from baths, showers and hand basins, domestic appliances and fittings. Black water is fouled water from toilets and bidets. The grey water that can be recycled is approximately 26% of the average consumption in a domestic dwelling (or 47% if the washing machine is included). The water used for toilet flushing is approximately 33% and outside use is approximately 3% of the average consumption. Grey water for toilet flushing can be supplemented by mains or rain water. The pay back time for grey water systems using waste water for toilet flushing is between 7 and 15 years depending on capital costs (E500- El,OOO) and based on an average price of E1.28 per M3. The pay back time is reduced to 4-8 years in the South West where the price per M3 is E2.30. The payback time for grey water systems is shorter than rainwater systems but the manufacturers/installers need to consider the end users perception and attitude, health and safety aspects and legislation and planning permission." Envirosink "Envirosink is an environmentally helpful additional, or secondary sink that utilises all standard plumbing fittings. Envirosink allows you to conserve the 'light' gray water from your kitchen. Envirosink is the only system that allows some catchment of water at the kitchen sink -- to help fill your rain barrel in the dry season." Bermuda "Here in Bermuda all residential properties catch rainwater on the roof. This is constructed oflapped limestone slate on a timber frame. The water collected drains down into a water tank which is located beneath the house. The general rule of thumb is that the tank must be large enough to hold, in gallons, an amount calculated by multiplying the roof area of the house by eight and a quarter. This water collection system has been in use for many, many years." (Department of Planning, Bermuda) Department of Planning Government Administration Building 30 Parliament Street, Hamilton HM12, Bermuda Phone: (809) 295-5151 Fax: (809) 295-4100 Rainwater Collection Systems Videotape and Booklet, revised 1995 Morris Media Associates, Inc. 4306 Wildridge Circle Austin, Texas 78759 USA http://www.cityfarmer.org/rainbarre172.html 09/08/2001 'City Farmer:Rain Barrels Page 8 of8 "Rainwater Collection Systems is the story of three families from the Texas Hill Country who collect rainwater for all their household needs, including drinking. And they would say 'especially' drinking! 'When emergency room physician Dr. Mike McElveen and his wife Kathy decided to collect enough rainwater for all their needs, their system became the model for others in their area to follow. A 50 page booklet accompanies each half-hour video.' Emergency Water, Soft Water, Chemical Free Water from Plastmo Non mechanical rain water diyerter used to collect water for chlorine sensitive plants. New Feature! Search Our Site ,~~~ ~ Return to Contents' Page ~ Revised May 28, 2001 Published by City Farmer Canada's Office of Urban Agriculture ci tyfarm@interchan~_ubc~a http://www.cityfarmer .org/rainbarrel72.html 09/08/2001 Rain Gardens Page 1 of 9 Visit the 'Fdends of Bassett Creek' Website ---- Rain Gardens ---- - - - - This Raingarden Pamphlet in Adobe Acrobat PDF Format (1.2m) - - - - Gardening with Water Quality in Mind When you make a garden a "rain garden" you can improve local water quality while creating a beautiful natural area that will attract birds and butterflies. Rain gardens allow rain and snowmelt to seep naturally into the ground. This helps recharge our groundwater supply, and prevents a water quality problem called polluted runoff. Rain gardens are an important way to make our cities more attractive places to live while building urban ecological health. What makes a garden a rain garden? All it takes is a few simple steps in the following three areas: Landscaping: ~ Rain gardens are designed with a dip at the center to collect rain and - snow melt. Any degree of indentation is useful, from slight dips made with your garden trowel to large swales created by professional landscapers. Neatly trimmed shrubs, a crisp edge of lawn, stone retaining walls and other devices can be used to keep garden edges neat and visually appealing. Location: . http://www.mninter.net/~stack/rain/index.htm 09/08/2001 Rain Gardens Page 2 of 9 Strategic placement next to hard surfaces such as alleys, sidewalks, driveways and under gutters makes your rain garden effective. Following you will find descriptions for how rain gardens can work in the front, side and back sections of your property. Plant choices: Hardy native species that thrive in our ecosystem without chemical fertilizers and pesticides are the best choices. Many rain gardens feature shrubs as well as wild flowers and grasses. As a rule, the less "turf' on lawns, the better it is from a water quality stand point -- turf- style lawns create a harder surface which does not absorb water as readily as garden areas. Also, turf-style lawns often require chemical treatments and extra water to look uniform. Yards that feature native plants, grasses and shrubs are much easier to maintain. . -..- ..... . ..........----....... _n .......... .--.-.-.-.............-.--.......__....... ,..._._................_........_..._..... _____............_.____.._.............._..........n.__ .____........................._..__.....__._...._..___.............._....____.............".._____...._........._......... .._..__.. .. ..u..__m..........n ..............._ "..._...___.. What is polluted runoff? Polluted runoff is a big problem in urban areas where much of the ground is covered with hard surfaces such as roofs, streets, parking lots and sidewalks. Before development, rain and snow melt seeped slowly into the earth. Now water flows quickly across hard surfaces, picking up pollutants -- from organic particles, pesticides, fertilizers, gas, oil and other types of residue -- before dumping into storm drains. Once in the storm sewer system the water flows into local lakes and streams. In most cases it is not treated or cleaned in any way. Here in the Twin Cities almost all storm water eventually ends up in the Mississippi River -- our precious, world-class resource that is also the source of much of our drinking water. ,..........-..........-.---......--......-...--.--.,.---.-...-..-.--..........--.......--.....-....-.--...-.......--.........----..---.-.-....-..-.....----.--.-.---'------..----...-.----.--..----.....---....---..--.--.-..-.........-..--...... Front yard gardens: Gardens along the front of homes and businesses are particularly useful from a water quality and aesthetic standpoint. Their proximity to the street makes front yard gardens an effective place to collect water that has run off of your roof, yard, driveway and sidewalk before it hits the stormwater system. Because they are highly visible to people passing by . http:j jwww.mninter.netj~stackjrainjindex.htm 09/08/2001 Rain Gardens Page 3 of 9 on the street or sidewalk, front yard raingardens also add to the beauty of the neighborhood. . If the rainwater collection area is larger and the raingarden smaller, . http://www.mninter.net/~stack/rain/index.htm 09/08/2001 Rain Gardens Page 4 of 9 then in some cases overflow or excess standing water may become a problem. Small culverts and/or swales may be useful in these cases to move excess water from one raingarden to another that has extra capacity. There may even be a community raingarden that receives water from a number of adjacent properties. Front yard gardens can be created: · At the end of the roof gutter to capture run off from the roof. . Along front walkway to keep runoff from traveling down the sidewalk and into the storm sewer. . Along the city sidewalk to act as a buffer between your lawn and the street. . · On the city-owned boulevard to stop runoff from entering the street. Property owners with front yards that slope to the sidewalk may choose to incorporate stone walls. With the addition of wall features, collection points can become deeper and more useful from a water filtration stand point. If the wall is decorative and combined with neatly edged turf, the area will be beautiful throughout the year. Side yard gardens: Gardens along the side of your home or business can catch runoff from your roof, create a "living fence" between properties and channel runoff to front or back yard gardens. Some homeowners create wide side yard gardens that become wider still in the back yard. This style of garden can minimize the amount of "turf' in your back yard that needs to be mowed. Creating wild areas along the side of your house ensures that you can look out your window and see beautiful plants, birds and butterflies. Don't plant tall shrubs right next to your windows if you are concerned about people hiding there. Also, make sure dips for . capturing runoff channel water away from your house to avoid basement flooding problems. :Back yard gardens: Back yard gardens can keep water from running down the alley and into storm sewers. Like side yard gardens, back yard gardens can also help minimize the amount of high-maintenance turf-style lawn on your property. Most people place their largest gardens in the back yard. If . http://www.mninter.net/....stack/rain/index.htm 09/08/2001 Rain Gardens Page 5 of 9 you already have a large back yard garden, you can easily add a water filtration component by creating dips that will hold and filter water. . In any location, a rain garden's basic feature is a dip or swale. Shrubs are often planted at the center and surrounded by wild flowers. Q: - How do I turn a section of my yard into a rain garden? A: - Simply remove sod, dig a shallow depression and plant with native plants. Q: - Don't rain gardens attract a lot of mosquitoes? A: - Not really. Mosquitoes thrive and breed in standing water. Most mosquitoes breed in places like junk-piles where there are old tires or tin cans. There is rarely standing water in a well-designed rain garden. Q: - Can I create a rain garden that doesn't look too wild or messy? A: - The way to make a rain garden, or any garden, appear 'well kept' is to keep the edges tidy. Tall plants and grasses tend to "flop-over" so if you want a neat silhouette, you will want to stick with short species. To keep native plants from growing too large, remember not to water them! Q: - What happens to water-tolerant plants when we have a dry spell? A: - Native plants can withstand a range of weather conditions. Native plants that do well in poorly drained soil will be fine during dry weather, > Q: - How large must a rain garden be to be worthwhile? http://www.mninter.net/-stack/rain/index.htm 09/08/2001 Rain Gardens Page 6 of 9 A: - Any water that seeps into the ground instead of running into a storm sewer helps water quality. A rain garden of any size has a positive impact. .---- - . ~_. Neighborhood raingardens can provide recreation opportunities, re- create wetlands and add aesthetic value to our urban communities. Neighborhood Projects: The overall landscape pattern of our cities includes easements and small public properties. These areas are ideal for gardens that improve the ecological functioning and the aesthetic value of our communities. In the Twin Cities, our proximity to the Mississippi River and its network of tributary creeks and streams provides many opportunities for protecting this great waterway through restoration of former natural areas. Across the country, urban communities are realizing the economic, social and environmental benefits of creating stormwater filtration projects and restoring native vegetation. Twin City based efforts include work in the neighborhoods surrounding St. Paul's Lower Phalen Creek and Minneapolis' Bassett Creek -- Mississippi River tributaries that have been degraded and partially buried as storm sewers. Residents, businesses, employees and government agencies are working together to recreate natural areas and improve water quality in Lower Phalen Creek and Bassett Creek. Efforts, which are spearheaded by St. Paul's Friends of Swede Hollow and Minneapolis' Friends of Bassett Creek, include promoting rain gardens as well as: . Recreating wetlands and other natural areas. . Improving and enhancing existing parks and natural areas through removal of invasive trees, planting of native species and increasing public access. . Creating and extending public bicycle and pedestrian trails to provide new recreation opportunities and connections to the Mississippi River. Rain gardens in action! . http://www.mninter.net/--stack/rain/index.htm 09/08/2001 Rain Gardens Page 7 of 9 There are a number of sites where rain gardens are being installed to add beauty to our cities while capturing and filtering stormwater. Friends of Swede Hollow and the City of St. Paul are installing a rain garden demonstration site on Seventh Street near the Swede Hollow Cafe. The St. Paul Neighborhood Energy Consortium is building a rain garden at their new site on Selby and Dale. Through this project, an existing parking lot's impervious surfaces are being reduced by about 17 percent. To see a residential rain garden, take a look at the yard on 118 Virginia Street (one half block north of Summit Avenue, near Western in St. Paul). The rain garden is visible from the sidewalk. Native Plants for Rain Gardens Below is a list of native plant and shrub options for wet soils in the center of rain gardens: Native Plants for Wet Soils --- Sunn}( Areas: · Sweet Flag - - - = - - - - (Acorus ~alamus) · Giant Hyssop* - - - - - - (Agastache foeniculum) · Canada Anemone - - - - (Anemone canadensis) · Marsh Milkweed* - - - = (Asclepias incarnata) . New England Aster* - - (Aster novae-angliae) · Marsh Marigold - - - - (Caltha palustis) . Tussock Sedge - - - - (Carex stricta) . Turtlehead* - - = - = - (Chelone glabra) · Joe JOre Weed* - - - - - (Eupatorium maculatum) · Boneset - - = - = - : - (Eupatorium perfoliatum) -. Queen Qf the Prairie* = (Filipendula rubra} = · Sneezeweed - - - = - - (Helenium autumn ale ) · Blueflag lris - - - - - - (Iris versicolor) · Soft Rush - - - - - - - GI uncus effusus) · Great Blue .Lobelia = - (Lobelia siphilitica) · Switchgrass* = = - = - = {Panicum yirgatum} · Prairie Phlox = = - = - = (Phlox nilosa) . http://www.mninter.net/-stack/rain/index.htm 09/08/2001 . Rain Gardens . Mountain Mint - - - - - (Pycnanthemum virginianum) . River Bulrush - - - - - (Scirpus fluviatilis) . Softstem Bulrush - - - (Scirpus validus} . Riddell's Goldenrod - - (Solidago riddellii) . Tall Meadow Rue* - - - (Thalictrum dasycarpum) . Culvers Root* - - - - - (Yeronicastrum virginicum) . Golden Alexander - - - (Zizia aurea) Native Plants for Wet Soils --- Shad}! Areas: . Caterpiller Sedge - - - (Carex crinita} . Cardinal Flower*.:.:.: - (Lobelia~ardinalis) . Ostrich Fern* - - - - - (Matteuccia struthiopteris) . Virginia Bluebells - - - (Mertensia verginica) . Sensitive Fern: - - - - (Qnoclea ~ensibilis) *Likely to grow taller than three feet. Shrubs --- Sunny or Shady Areas: . Black Chokeberry - - - (Aronia melanocarpa) . Red Osier Dogwood - - (Cornus serecia} . Low Bush Honeysuckle - (Diervilla lonicera) · Annabelle Hydrangea - - (Hydrangea arborescense 'Annabelle') . Eussy Willow - - - - - (Salix caprea) . Blue Arctic Willow - - - (Salix purpurea 'Nanna') Shrubs --- Sunny Areas Onlle- . Meadow Sweet - - - - (Spiraea alba) · Steeplebush - - .: - - - (Spiraea 10mentosa) . High Bush Cranberry - (Viburnum trilobum) - For purchasing native plants and seeds: · -Prairie Restorations Inc: 888-389-4342 · Landscape Alternatives: 651-488-3142 · Prairie Moon Nursery (mail order only): 507-452-1362 - http://www.mninter.net/~stack/rain/index.htm Page 8 of 9 09/08/2001 , Rain Gardens Page 9 of9 For information on gardening with native plants, runoff pollution prevention and workshop opportunities, call the St Paul Neighborhood Energy Consortium: 651--644-7678 For information on native plant demonstration sites, classes, youth gardening projects or starting a community garden, call the Sustainable Resources Center Urban Lands Program: 612--872-3288 Read 12l1blished newspa12er article on a neighborhood rain gardens retrofittil1g-I2mi~t along a city street~ Some Rain Garden Links: =::- Environmental Protection Agency (EP A) urban runoff and rain gardens. ==-Rul1offtreatment and rain..gardens at Jordan Cove. Connecticut (EPA). =--:- Rain.gardens q,t Port Towns, Maryland. :--- Rain_gardens at the Virgi!lia Department of Forestry Native plant information was supplied by Fred Rozumalski, Barr Engineerill9. Rain garden text written primarily by Amy Middleton and Sarah Clark. Funding for this rain garden pamphlet was provided by the McKnight .Foundation. Minn~gna Oellartmem of Natural Resources and Minn~ta Office of Environmental Assistance. Illustrations reprinted courtesy University of Minnesota Department of Landscape Architecture. (Maintained by Dave Stack, Ed McRoberts ;Content@ Friends of Bassett Creek; (Created by Gabe Ormsby); Update 01feb13) Please em ail usatstack@mninter.netif you notice any links or phone contacts on this website that have died. . http://www.mninter.net/-stack/rain/index.htm 09/08/2001 Demostration Site, Driveway Dry Well D. Driveway Dry Well This drywell system serves the dual purpose of retaining and cleansing rainwater, giving it time to percolate into the ground rather than carrying motor oil and other pollutants into the storm drain system and out to our beaches and bays. Rainwater flowing down the driveway runs through a grate (see D) into a box containing sand and crushed rock that captures pollutants. ReturnJo Demo!lstrati9n Site . http://www.treepeople.org/trees/d.htm Click here to view Actual Sit~ (Size 80kh) .;I'~~.t~. II' '!l~I!.. 4t... I Page 1 of 1 09/08/2001 HARDSHIP CRITERIA Hardship criteria # l. The lot was developed before applicant purchased it and he upgraded the existing house, under permit. The "calculations" desired by staff are not relevant as per the engineer's letter dated December 6 and presented to the Commission prior to the December 10 meeting. No alternatives have been offered by the engineering department, although I spoke with Lani Leichty and requested what they were considering. There are practical difficulties with this lot which the current owner did not create. He has enhanced the property in line with the surrounding neighborhood and has the full support of his neighbors in his efforts. Hardship criteria #1 is met. #2. The need for the rear patio was documented, at the request of the Planning Commission. The chronology, attached, reflects the misrepresentation made by the Planning staff on the ability -10 bring in the requested information. Not the fir~t mi<:repreSlent~ti()n they have made as is indicated_ in my sh..grt list, developed d:.!!i~~olvement in this case. The setback variance 'granted from the 1akeshore required Mr. Crouse to stabilize his backfill when the house was raised to meet current code. Hardship criteria #2 is met. #3. Reasonable use includes protecting the stability of structures and erosion control. Mr. Crouse's property would be devalued and possibly compromised should the patio be removed. While variance approval after the fact is not typical or encouraged, destruction can be construed as a taking. Hardship criteria #3 is met. #4. Staff, Mr. Crouse and his neighbors are in full agreement that this is not a problem. Hardship criteria #4 is met. #5. The impervious surface of the patio creates minimal drainage impact, according to Pat Lynch ofthe DNR. Removal of the stabilizing surface could create major erosion problems, not the infiltration area Staff envisions. More effective is an alternate drainage system for which Mr. Crouse's house is set up for now. Removal of the patio will impact property values and impair establish~q__PIQI?~ill'"y'al~s. --- Hardship criteria #5 is met, removal of the patio will diminish property value and impact the neighborhood, creating hardship on the community. #6. The intent of variances is to allow flexibility with Ordinances and to give municipalities the ability to improve while maintaining standards. No one can dispute that Mr. Crouse has improved his property. The entire neighborhood is behind his efforts. His lot is adjacent to an open outlot which creates a large pervious infiltration area and is one of the reasons his lot is small. The intent of the Ordinance and Comprehensive Plan is to create a standard and encourage improvement of real property in concert with surrounding properties. Mr. Crouse has brought his property in line with his neighborhood - the intent of the Plan! Hardship criteria #6 is met. #7. No other means have been identified by City Engineering to stabilize Mr. Crouse's patio area. He raised the house to meet Code requirements that had changed from when the house was originally built, creating the need for backfill. The close proximity to the lake (per granted variance) requires the backfill be stabilized. This is not convenience for the property owner, it is protection. Hardship criteria #7 is met. #8. The hardship results from: - Ordinance changes requiring a driveway be calculated as impervious surface (see attached November 22, 1996 letter documenting change) - Code changes requiring a higher elevation for lower levels - Platting which created an undersized and irregular lot prior to impervious surface limitations Hardship criteria #8 is met. #9. Economic considerations alone are not sufficient to grant a variance. However, the expense to create another cap, which functions at/or about the same level as the current cap, can and should be considered when making a decision on Mr. Crouse's variance request. However, Mr. Crouse is willing to expend resources to use alternative methods to mitigate the runoff and monitor it. His house is ideally set up for this type of mitigation because all guttering and downspouting is in place. The 28% could be captured easily and managed through rainbarrels and other mechanisms. From a 46.4% unmanaged runoff, it would result in 18.4% resiaual. NOVENffiER 22, 1996 Dear Builder/Surveyor: On November 18, 1996 the Prior Lake City Council adopted an ordinance modifying the definition of impervious surface. The change adds gravel driveways to the defInition of impervious surface. The effect of this on new construction will be irrelevant, as paved driveways are required on new construction. The effect on existing parcels could be signifIcant in some cases. The new detinition is as follows: Iil-[PERVTOUS SURFACE: Tlteportion of the buildahleparcel which has a covering which does not permit water to percolate into the natural soiL Impervious surface shall include, but not be limited to, all driveways and parking areas, whether paved or not, sidewalks greater tItan 3' in width, patios, tennis and hasketball courts, swimming pools, covered decks and other structures. Decks open to the sky and having open joints of at least one-fourth inch (1/4") and sidewalks 3' in width or less shall be e.'Cemptedfrom the calculation of impervious surface. TIle impervious surface of a lot shall be documented by a certificate of survey unless e.'Cemptedfrqm this requirement by tlte Zoning Administrator. In order to better administer the impervious surface requirements, the City has created a worksheet to be submitted with all building permit applications for property located. in the Shoreland District (SD). The impervious surface requirement only applies to property located in the Shoreland District. The Shoreland District includes all property located within 1,000 feet of a significant body of water such as Prior Lake, Spring Lake, Mystic Lake, Markley Lake, etc. and the tributaries leading to them. If you are unsure of the zoning, please call us. Please feel free to call us if you have questions regarding the worksheet. Thank. you for your cooperation. Sincerely, (\ M AA.i J {/II~/U ~;~;~ Planner IMPL TR.DOC/JKT 16200 Eagle Creek Ave. S.E.. Prior Lake. Minnesota 55372-1714 I Ph. (612) 447-4230 I Fax (612) 447-4245 AN EQL'AL OPPORTI.':"lTY ~;.lPlOYER 2/23/01 6/25/01 7/23/01 9/10/01 9/14/01 9/24/01 9/25/01 10/5/01 10/8/01 ' CHRONOLOGY Crouse Variance Request Mr. Crouse files original variance application (57.5% impervious surface) Hearing held Hearing scheduled but applicant out of town, postponed Hearing with representative appearing for Mr. Crouse (business trip) 45% discussed at June 25 meeting, 44% proposal presented, with alternative measures to bring infiltration below 30%, motion made for 40%,36% passed with need for additional information emphasized. Letter of appeal of 36% variance fIled with Don Rye Planning Commission meeting - Resolution modifIed from 36% to 38% without public hearing _ ~ ck 3~"k' Telephone call from Steve Horsman - ready to publish~ut nothing final until Resolution signed at October 8 Commission meeting. Based on Horsman's request, letter sent withdrawing appeal so that additional engineering information could be introduced to Commissioners and the City for this variance. Based on Horsman's representations - engineers report sent to all Commissioners and the City with request public hearing be reopened to introduce this information. Letter faxed from the City denying request to introduce additional information and requiring a new variance. Hearing held and Resolution signed for 38% variance. Examples: Teilborg's surprise at having to remove garage (Sept. 10 Planning Commission mtg) Norling's change to their variance without public hearing (post-approval) Crouse's denial to reopen hearing and subsequent change in variance (post-approval) HUEMORIJl'JRR & BATES AITORNEYS AT LAW 16670 FRANKLIN TRAll. P.O. BOX 67 PRIOR LAKE, MINNEsOTA 55372 JAMES D. BATES BRYCE D. HUEMOELLER September 14,-2001 Telephone (952) 447-2131 Fax (952) 447-5628 Mr. Donald R. Rye Prior Lake Planning Director 16200 Eagle Creek Avenue Prior Lake MN 55372 Re: D. Mark Crouse - Application for Variance No. 01-017 Dear Mr. Rye: This letter is a notice of appeal to the Prior Lake City Council from the September 10, 2001 action by the Planning Commission reducing Mr. Crouse's variance application for increased impervious surface from 57.5% to 36%. Please send me copies of the Planning Commission's minutes and the staff report for the City Council meeting as they become available. Vt~ ~y yours..\ \.....-1 ~ I- I LL:""\I... ~ 1 .,. "rJ. 1)../..A.i~::- ,... ,,,,.' ....,~ ~-../ . -....-' Allison J. Gontarek Attorney at Law ~ I;' ., i i' II / :;.t..j:J...., h>~f( . , I -- "-"' cc: D. Mark CroUse HUEMOELLER & BATES ATTORNEYS AT LAW POST OFFICE BOX 67 PRIOR LAKE, MINNESOTA 55372 Telephone: 952.447.2131 Facsimile: 952.447.5628 E-mail: huemoellerbates(q?aol.com BRYCE D. HUEMOELLER JAMES D. BATES ALLISON J. GONTAREK OF COUNSEL: CHARLES C. HALBERG September 25,2001 Mr. Steve Horsman Prior Lake Planning Department 16200 Eagle Creek Avenue Prior Lake N1N 55372 By Facsimile and U.S. Mail Re: D. Mark Crouse - Application for Variance No. 01-017 Dear Mr. Horsman: Please consider this letter as a request for your department to disregard my September 14 letter of appeal directed to Mr. Rye, Planning Director. We were under the impression that a final decision had been reached at the September 10 Planning Commis,sion meeting which required an appeal within 5 days. I apologize for the . misunderstanding and appreciate you contacting me before publishing the notice. Thanks! Very truly yours, i '. I ',I \..LL I ~ ; ." i il-0'20t- Allison J. Gontarek HUEMOELLER & BATES ATTORNEYS AT LAW POST OFFICE BOX 67 PRIOR LAKE, MINNESOTA 55372 Telephone: 952.447.2131 Facsimile: 952.447.5628 E-mail: huemoellerbates@ao1.com BRYCE D. HUEMOELLER JAMES D. BATES ALLISON J. GONTAREK OF COUNSEL: CHARLES C. HALBERG October 5,2001 Mr. Steve Horsman Prior Lake Planning Department 16200 Eagle Creek Avenue Prior Lake :MN 55372 Hand Delivered Re: D. Mark Crouse - Application for Variance No. 01-017 Dear Mr. Horsman: Enclosed please find a report prepared by Professional Engineering Consultants regarding . the requirement for a cap between Mr. Crouse's house and the lakeshore. We respectfully request that the hearing on Mr. Crouse's variance request be reopened based on this new information, obtained at the request of the Planning Commission. This engineering analysis was obtained to satisfy the questions raised by the Planning Commission at their September 10,2001 meeting. It is in draft form because the engineering firm was unable to produce a final, more polished copy. I will forward you a final copy as soon as it becomes available. I am forwarding the report to all the Planning Commissioners individually in hopes to expedite a drawn out process. Mr. Gislason states the need for a cap was created by the legally permitted raising of the original structure to comply with current elevation requirements. We would appreciate the Planning Commission taking this additional information into consideration in Mr. Crouse's variance request. ..... V. FY: 1ruly yours, M . ./.~-jj[.Lc;p~ /~v~-rJ- Allison 1. Gontarek cc: D. Mark Crouse PLANNING REPORT SITE: PRESENTER: REVIEWED BY: PUBLIC HEARING: DATE: 4A CONSIDER A RESOLUTION APPROVING A VARIANCE FOR AN IMPERVIOUS SURFACE. COVERAGE AREA OF 38%, FOR D. MARK CROUSE, Case File #01-017PC 15507 CALMUT AVENUE NE STEVEN HORSMAN, ZONING ADMINISTRATOR JANE KANSIER, PLANNING COORDINATOR YES -L NO OCTOBER 8, 2001 AGENDA ITEM: SUBJECT: - INTRODUCTION: The Planning .Department received a variance application from property owner - Mr. D. Mark Crouse for an impervious surface coverage area of 4,422 square .feet or 57.5% of the total lot area on the property located at 15507 Catmut . Avenue NE (Attachment 1 - Certificate of Survey). The Planning Commission conducted public hearings on this item on June 25, 2001, on July 23, 2001, and on September 10, 2001. After review of the applicant's request with respect to the variance hardship criteria, the Planning Commission directed staff to draft a resolution approving a variance to allow an . impervious surface of 36 %. On September 24, 2001, the Planning Commission reconsidered their earlier action. The Commission determined a 36% impervious surface would not allow a driveway. The Commission therefore approved a 38% impervious surface and directed staff to prepare a resolution. 1-. A variance to permit an impervious surface coverage area of 38% of the lot area above the 904 foot elevation (OHWM), rather than the maximum allowable coverage of 30%. The following conditions must be adhered to as part of the Variance Resolution: 1. The applicant shall submit to the City of Prior Lake a revised certificate of survey identifying the impervious surface to remain on the lot and the 16200 Eagle Creek Ave. S.E., Prior Lake, Minnesota 55372-1714 / Ph. (952) 447-4230 / Fax (952) 447-4245 AN EQUAL OPPORTUNITY EMPLOYER ,__,_,~,,_,_'_~__""'_'~'_,~ "__~h__",_,_,,_,,___~,.,w"_"_'4. .._._,____."._..__~.,._.._..._....~"...,__._,._.._~~_~.~,___,___~_..,~_~__~...__..._. ........"_.............."'-'"---.......-,-~-_.~ October 8, 2001 Ms. Allison Gontarek Huemoeller & Bates 16670 Franklin Trail Prior Lake, MN 55372 Dear Ms. Gontarek: The City of Prior Lake received a letter from you dated October 5, 2001, requesting that the public hearing be reopened for Variance File 01-017PC. You included additional information from a Professional Engineering Consultant regarding the need for a cap (patio) between the home and lakeshore retaining wall on the. property at 15507 Calmut Avenue. As you are aware the Planning Commission made a final decision on this matter, and allowed the applicant to maintain a 38% impervious surface area on the subject property, at the scheduled hearing on September 24, 2001. This provides for a driveway to the 3-stall garage, but requires the additional impervious surface area to be removed, including the patio area in question. The public hearing for this request has been closed and any additional variance requests and supporting documentation shall be processed in the form of a new variance application. If you should have any questions regarding this matter, call my direct phone number at 447-9854 between 8:00 a.m. and 4:30 p.m., Monday through Friday, and I will assist you. Sincerely, Au~~ even Horsman Zoning Administrator/Inspector Enclosed: Variance Application 16200 ~~"l!reek Ave. S.E., Prior Lake, Minnesota 55372-1714 / Ph. (952) 447-4230 / Fax (952) 447-4245 AN EQUAL OPPORTUNITY EMPLOYER JAN.22'2002 15:25 651 770 2552 EMMONS << OLIVER RESOURCES #1704 P.002/010 January 22, 2002 ErR EMMONS & OLIVIER RESOU RCES ~ ......... ~- ~ -"_::~ Ms. Allison Gontarek, Esq. HlJemoelJer & Bates 16670 Franklin Trail Prior Lake, MN 55372 Re: Crouse Impervious MWgation Rain Barrel & Rain Garden Project Dear Ms. Gontarek: Thj,s submittal is a follow up to OUT recent telephone conversation. Enclosed you will find general infonnatio,n rel,ared to cont.ro1ling stonn water runoff volumes. Also we have quickly reviewed. the small-scale survey of the Crouse property and have included some brief recommendations. General Infonnation The fust item you will find is a 4-page draft fact sheet EOR has generated for a watershed district client. This fact sheet provides specific design cnten.a used for constructing infjJtration trenches, infiltration tubes and rain gardens. The second item enclosed is a general information sheet on infiltration. The third it.em is some generaJ information on rain barrels and ci,st.ems photocopied from a m.anual, called "Low-Impact Development Design st.rategies" prepared by Prince George's County, Maryland. Recommendations With the specific intent to mitigate the amount of stonn, water runoff generated by the impervious surfaces on the property we have developed the following conceptual ideas: 1. Rain barrels should be installed at roof downspouts. TIle rain barrels should be si1..ed toO collect and store at least the volume of water generated by any additional proposed impervious area for a two-year storm (2.5" in 24 hrs). For each 100 sq- ft of im ious surfac 56 aJJoos of stora e is required to retam a Z-year. - event. Typical rain barrels have a capacity of 42 g ons. ger storage umts are typicatly called cisterns and range from hundreds to thousands of gallons. St.ored water Call be retained for long periods of time and used for Jand.oqcap;n.g watering, car washing or with proper treatment, drinking. 2. Small-scale infilrration tren.ches and tubes may be incorporated in the landscaping plan without taking up a lot of space. Storm water nJ.noff should be directed to the designed strucrures allowing runoff to be infiltrated.. J..,Qcalion of designed infiltration structures must be considered carefully. Many factors such as soil type, proximity to stmctures and storage volume need to be considered. In many Making A Difference Through Integrated Resource Management EOR, INC. · 3825 Lal(r:! Elmo Avenue North · Lake Elmo, MN · 55042 · Tel: (651) 770-8448 · Fax: (651) 770-2552 JAN.22'2002 15:25 651 770 2552 EMMONS & OLIVER RESOURCES #1704 P.003/010 ca..o;es infiltration trenches blend in to site landscapin.g and in some cases can be const.ructed under im.pervious surfaces such as parking lots and driveways. This site wi.lI have t.o be further analyzed to d.etenni.ne the appropriateness of these types of infiltration practices. 3. Rain gardens should be incorporated into the landscaping plan. Rai.n gardens are planted with native flowers, grasses and shrubs tbat can tolerate period.s of saturation and drou.ght. Storm water roured to rajn gardens is stored, infiltra,ted and utilized. by tbe plants. 4. Native Jandscapi,ng should be incorporated into the landscaping design. Turf grasses on the property should be minimized as much as possible. Manicured turf grasses generate nearly as much stonn water runoff as im.pervious surfaces. Considerations should be gi.ven t.o replace conventional turf grass with native grasses and flowers. Including areas of native plantings in a site landscaping plan can considerably reduce the amount of storm water generated during a rain event and requires a lot Jess maintenance that traditional turf. Also, being that the site is on Prior Lakel native landscaping alon.g the shoreHne could provide pretreatment of storm water before it enters the lake. Next Steps We appreciar.e your interest in protecting our water resources through the use of ;nnovati,ve storrn water management practices. Please let us know if you would like additional information on these types of stonn water management practices or jf you require additional assistance in the future. Sincerely, ~C4 Camilla Correll Water Resource Engjneer ason R. Naber Natural Resource Specialist JAN.22'2002 15:26 651 770 2552 EMMONS DRAFT Infiltration Trench, Tube & Rain Garden INTRODUCTION TO PRACTICE An infiltration trench is an excavated depression that is ba.ckfilled with washed grovel providing underground storagE: for runoff allowing it to infiltrate into the underlying soil. Infiltration tubes are a variation of the trel'lch design. Rain gardens CO" be designed to include subsurface improvements like those of 0 trench. Due to their small slze, infiltration trencl1es, tubes Clnd rain gardens are appropriate for confined areas such as pa.rking rat islands, roadSide swales or residential sites. Infi Itrat;o" trenches and tubes can also be used as er1hancements in regional infiltration practices by allowing storm water to by- pass impermeable layers, such as clay lenses, thereby increasing the overall infiltratian capacity of tl1e facility. SITE SUITABILITY Infiltration trenches and tubes sholJld only be used in areas where 1'he following physical site characteristics are suitable: sail type and depth to the seasonally high water table, depth to bedrock or on impeding layer, contributing drainage area and topography. The following steps should be taken in the evaluation of site suitability: · Perform ane to three soil borings in the location of the infiltration practice(s) to confirm naturally occurring permeable soils, depth to the seasonally high water table, bedrock Or' an impeding layer. A minimum 3- foot distance should be provided below the bottom of the practice and the water table or bedrock (Protecting Water Quality in Urban Areas: A Manual, Minnesota Pollution Control Agency, March I, 2000). & OLIVER RESOURCES MAIN.:O$.!,ec1;lvES , ... . 'I' . ,. . :To::r;~~!;',s:~ ".p.e~~...fl~~.' rates ,a":g.,, r.u,noff volumes from dev~loped sites . t().:m~i,,+a,n' predevelapment 'i~Y9r?I~9Y~ . . 8301 VCllley Creek Road Woodbury, MN 55125 (651) 714.37Z~ · Determine haw suitable the topagraphy ;s for an infiltratian trench. These practices should not be constructed on sites with a slope greater tl1an 20 percent, · According to the literature, the contributing drainage area to an infiltration trench or tube typically should not exceed five acres. ~ Evaluate the impact of constructing an infiltration practice on existing hydrologic featlJreS (e.g. wetlands) and try to maintain pre-existing conditions (e.g. do not breach a perched water table. which is supporting a wetland). Figure 1, Excavo.tion of o.n infiltration tre.nch with a backhoe. Note: Based on past experience with current regulations, infiltration tubes may be classified as Class V Injection Wells and must be registered with the MPCA. As long as hazardous substances are not anticipated in the runoff and the tube is not withi" three feet of the water table, the registration process is fairly simple. JAN,22'2002 15:26 651 770 2552 --..... . EMMONS & OLIVER RESOURCES #1704 E'.005/010 r-""-:." " J : ~ ,"""", ,. . -: ;:- ,II " ~ ; .. ~ :~~1~ ", "J ," Figure 2. Post construction photo of infiltration trench with observation well. RECOMMENDA TrONS FROM LOCAL CONTRACTORS I DEVELOPERS AND CITY STAFF "Would like to see more. infiltration practices being IJsed upstream in the system (e.g. creating islands or green spar.es adJClcent to parking areas) rather than diverting 011 of the runoff to (J regIonal facility." "Detoils should reflect the soil conditions found on site." "Engineer approved alternate" is an important thing to include in the detai Is because the supplier might know of another source or alternative the contractor could IJSe. "Recommend plClcing the filter fabric a foot below the surface to avoid future disturbance to tl1e fabric." "Dry wells require pretreatment otnerwise they silt up and the only way to clean them is to dig them up and replace. them." "The observation well is a good ideo because you con see if the infiltration practice is working and you can install it inexpellsively." SITE SELECTION · Permeable Soils - Naturally occurring permeable soils should be confirmed by performing soil borings in the location of the infiltration practice(s). Sources of i"formation include: the Soil Survey of Washington and Ramsey Counties (1977), the Geolog;c Atlas (1990) and the South . Wl'Jshi"9t()n WClter~h~ Di~,.ict Infiltrl'Jtion Monagem~t Map. Depth to Seasonally High Wcrter Table and Bedroek - Verify that a sufficient depth from the bottom of the infiltration tret'lch, tube or rain garden to the seasonally high water table ;s maintained. According to the M;n",~soto Pollution Control Agency Protecting Water Quality in Urban Areos: A MtJnua! Q minimum three-foot distance should be provided from the bottom of the infiltration practice to the seasonally high water table bedrock or on impeding layer. DESIGN CONSIDERA TIONS · Proximity to Wells and Foundations - Maintain Q 100-foot distance from drInking water wells and situate at least 10 feet down-gradient and 100-feet up gradient from building foundations. · Topography and Slope - Infiltration tret1ches should not be constructed on sites with a slope greater than 20 percent. · Contributing Oralnage Area. the contributing drainage area to an infiltration trench or a tube typically should not exceed five acres. · Maintain Pre.Developrnent Hydrology Infiltration trenches, tubes and rain gardens can be designed to provide the vollJme control required to offset the introduction of Imperviousness on a site thus maintoining pre~ development conditions. · Pretreatment of Runoff - Provide for the pretreatment of stormwater to prevent the infiltration trenel'l, tube or rai" garden from clogging prematurely. Vegetated buffers 0.101'19 the trench perimeter, pretreatment cells or small depressions to allow for the settling of sediment upstream of the infiltration practices are common pretreatmen1' tech"iqlJe5. · Maximum Oraining Time Infiltration trenches should be designed to droin within 72 hours after the design event to maintoin aerobic conditions in the underlying soils, otherwise biological clogging can become a problem. · Aggregate Maferial - Use 1-3 inch clean washed stone aggregate that is open-graded JAN.22'2002 15:26 651 770 2552 unA,., and of a narrow si%~ range so 'l1ot the voidll betweetl aggregates are not filled by slT1CIller particles thus co"tributing' to lower efficiencies or dogging of the practice. EMMONS & OLIVER RESOURCES w Filter Fabric - Filter fobric, wne.n necessary, should be permeable and should have a transmissivity of no less thon 100 gallons per minute. . Observation Well - An observation well (see detail) should be installed in each infiltration trench to monitor and evaluate the performance of the practice (e.g. 4" PVC pipe with t" slots, a screw on PVC cap and aluminum foot plate). Maintenance Access - Provide access for futlJre maintenance of the infiltration tretlch, tube or rain garden. . CONSTRUCTION METHODS . Grading Equipment - Infiltration trencl1es, tubes and rain gardens should be excavated using light earth moving ~ujpment 'to prevent 'the compaction of underlying soils (e.g. wide- 'tracked dozer, backhoe or other low- compaction equipment). Construction traffic should be routed away from these areas. Before site grading begins. place orange construction safety fence arolJnd the infiltration area 'to eliminate compaction of the soils similar to septic drain fields. Timing of Construction - The infiltration trench, tube or rein garden should not be constructed until the contributing drainage area has been constructed Clnd fully stabilized. This may r~uire re-mobilizatlon of equipment. Erosion Control - During construction of the infiltration trench, tube or rain garden, rigorous sediment and erosion controls (e.g. diversion berms) snorJld be used to keep sediment and runoff completely away from the infiltration area. Other Utilities - Avoid placing other utilities, such as sewer and water, within or under the infiltration practice. This avoids compactions and the potential for cross contamina'tion. . . . #1704 P.006/010 TIPS FOR CONSTRUCTION PLANS AND SPECIFICA TrONS For clarity. provide detailed information regarding the design end constrlJction of infiltration trenches, tubes and rain gardens on both the construction plans and specifications. This is importC1l"lt in the event tJ,at the plan set or project gets sp/i't up and the contractor ends up constructing tJ,e project with the plans only. The following type of lonsuage may be included in both the plans and specifications: 1. "Prior to grading, place orange construction safety fence. along the perimeter of the infiltration area to prevent compaction of the soils. " 2. "If preliminary grading of the infiltration area is absolutely necessory, grade the infiltration practice to within 3 to 5 feet of final grade to prevent compaction or clogging of the underlying soils," 3. "DO NOT excavate infiltration areas for borrow materiaL" 4. "Remove excavated soils and materials from infiltration area(s) to prevent erosion 1:>0<:1< into the infiltration practice and soil clogging." 5. .Protection of soils in infiltration areas refers to no compaction and preventing siltation." 6. "Seeding/restoration/planting of infiltration areas to be completed within 24 to 48 hours of final grading." MAINTENANCE NEEDS The maintenance of infiltration practices is an important factor in ensuring the long-'term perforlTlClnc;e: of an infiltration practice. Short-term maintenance requirements include vegetation management. debris removal, and sediment removal. Long-term maintenance requirements con include removal and replacement of overlying filter (see Figure 2) or rehabilitation of the entire practice jf it is clogged wit" sediment. The need to perform long-term mClintenance may be indicated by conducting rorJtine inspection using 1'he observation well. JAN.22.2002 15:27 651 770 2552 UnA,.., One of the main concerns with the maintenonce of infiltration practices is determining the respotlsible party or individual. InfiltratIon practices usually require a legally binding operation and maintenance agreement which would be included in the property deed. EMMONS & OLIVER RESOURCES TYPICAL COSTS OF CONSTRUCTION The followin9 construction costs for infiltration trenches and tubes are based upon practices that ha.ve been construded in the South Washin9ton Watershed District (1998-1999). These costs include the following: mobilization, excavation, hauling excess material off-site, constrlJction, observation well, and post-construction grading. Table 1. Construction Costs for Trellcnes & Tubes. Infi Itration Approximate Construction Practice Dimensions Cost Tube 2' diameter tube $4,100 Avg. Depth 12' Trench 9' W x 36' L $ B, 700 (Regional Setti"g) Avg. Depth 13' Trench 8' W x 15' 1_ x $4,900 (Local Setting) 10'D EXAMPLE DETAILS The following details were used in the construction of the infiltration trenches and tubes located in the SWWD. Site analysis ;s required for the design of specific infiltration practices. Figure 3. Infiltration Tube Design Detail ~~I~_1; 1:1'" '(110""" ~l......l -"'I/II'U ...:.., 10 v.......flP'lo Nil ,..., "'WlMIl ..,,, ...r.~1.t_ ~. 'r.'I'"".I$..n .."''''''''..'11..;...1''....,.01 Ll'" WIIIlIW:; ~~~~~ ., (..,. III IW.1f I....~ ril?;"'~ I /'1 .....,.:' ,w:~~~;:q '. .&irWn_~~=:..IL ", '._~: l~~~ \ ' " .~~... 11II'11:1Il ,.. j 'j' .,:/...".,....., "...".",._~.". .' .o.~}:>.:::.rt ."" ".. "~"""""'IlJ ,.' .. '" ~~t' fl'" ". . 111."11',1I Il'''l~ Figure 4. Infiltration Trenc" Design Detail #1704 P.007/010 , A .r"..v.lm lIlIr.r1t't4'M<- . --...---.............::,..-.. . .~' ,~...."....~J"I''''..,'I.JI -. o,S'1..' L' .,,. .l.._,..~:...J..._.~-,.l"."",.- C...~ J..... ./.._. .[:::'~:" ,.'':';., :'.;.:~ ~ .._:'1 ...:":'...P'";"'n,~.~. ...., ,", ,. ;";" . J -.~'" '\>~ .',." 0." '. . . 0", ...,..,'_~_" -i;... ..:~,,'~~,~~:~::~::...: :::.:::.<..t ",::,~;'</ >:~:.~'t'~~' ;>-'. '\ "':.,: .....', '., \. . .,>'- J........., \, "'., :.,', ....:.:..C ~~_.) I \ "'\1'lV......,j I:."... I " '''CO''.loQiJlo ."'AIJl;I" ".I~~..." \. -'.UtMtl'I....""'''"'' .. ....."61"rOOl'tC/'llO.l>ItltC, 1*'~,l{j1"'4wt) w".tklllll .' .. ~':~::::,l:.. ~.". ..- .,.....,.... ..,......, ( " .'. . . . 1M"'to..1I\.... I .."" ...... ~ ;.: -;::.:, .," " . I r~ ~l>U ....._..... ".....:~~\..~:~~~\.~"j~\:-~ (, II ( ._..-.-c-....::, l\';Jr.Jlf :rrll' ...:-'" ~J.:.~\}~:\;.':'\~\r~.~',~\,'~.I~Il-:.. r '.... ~.... .." ..... ~':'.l'.~.~X::: '.::~\~11:..~:f"i.f.'... ,." , "'':., . . '" ".... ~ ....... ." ..r.I~...~\I.:~.:\\,~\\~\.L...' " 1.i';~.~.. .~.!: ~'l!;" :~1.\\~i~t>.:;\i,. '~'.\. .' " ..' ,J ~~~';I;.~..... ':;J;.'. :..' .." 1...~~,Ll );,:'.:;<.::': ,..~. .~: .-- .~..-" ,. ", , .~. ,\',1, ..... .....,.. 1"'!If........ " ....~.~ l . .... .- ...,...... .""",.,. '.'.'" "Or.r.llfitU~~""lOAl."l.IlII ADDITIONAL RESOURCES The following materials provide additional information regarding the design and co"structio" of infiltration trenches, dry wells or rain gardens. 1. Controlling Urban Runoff: A Practicar Manual for Planning and Designing Urban BMP's. T.R. Schueler. Metropolitan Washington Council of Governments, Department of Environmental Programs. Washington, DC. 1987. 2. Low Impact Development Design Strategies: An Integrated Design Approach. Prince George's Cou"ty, Maryland Department of Environmental Resources. JC1J1uory 2000. . J. Rain Garden Reference to be added. CONTACT INFORMATION Camilla Correll Emmons & Olivier Resources, Inc. 3825 Lake Elmo Avenue North Lake Elmo, MN 55042 (651) 770.8448 ccorrell@eorinc.com JAN.22'2002 15:27 651 770 2552 EMMONS & OLIVER RESOURCES #1704 P.008/010 Mabing A Difference Through Integrated Resource Management EMMONS & OLIVIER RESOU RCES . EOR Is one of the leading firrm In Minnesota specializing In Water Resources EngIneering, Naturr::rl Resource Management, Hydrogeologic Services and Watershed Planning and Management INFILTRATION: AN ALTERNATIVE STORMWATER MANACEMENT TECHNIQUE lIIe ... .. ....1........ In ..........., ............. ............ ... ..........." ...... ......Ic. thai ...........n. tho ........-.k ""lanc. In d...I..... ............. IIItR..aIt... IV..... ..... 1M .,........ .. . ........, .. .... MIll. bv In...potal.... tho ..I...... ............. . 1II.....ln. M.......llnfllb...... B..In. · Infiltration ',onch../Drp W.II. · ...,et..t_ Ar... · St........, Pr..,.......... · V......IOII/............... PI... ........c le Inflltr...... In'IIb"I.n ".... .... 1M -aaral .... with . hlg. Infl......n .......JI, .......... a. ..... _. . ............ ,......1.1t ..... In .ho ......n laneI...... 1It'......lon ....... can .... ... cOlldrllClotl. .0. h ...." ............... In ..... .at....1 and dnIChIral Wl.rat.... ............ .......... .......ope.r . co....'.h.n.... ......It....... .f tho l.fl...lo. pr...... Ih.... ....n.... 'loId lIIala ........... ..... IJr. ......., _ndrlldl.. and ....n....... "Infllbatlon p,actf... ..,;) -.; . "'..",...~ ,.... I . 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Grassed Swa/e Design Considerations Channel Capacity Soils Channel Shape Bottom Width Side Slopes Channel LongiT.lJdinlll Slope Flow Dept.h Manning's n value Flow Velocity length of channel Water QUolllity Maintenance Determined by state or local agency. Refer to guidance provided by the Prince George's County 1.10 Design Manual and tl1e Maryland Stormwater Design Manual (MDE, 1998). lr.Jeal condition may necessitate adjustment of the rec:ommendations in the guidance documents. Swale must be $lzed to convey the peak dischllrge of the deSign storm The permeabiJity (infiltrlltion rllte) of th'? soils will determine whether a dry or wet swale can be IJsed. It is recommendEd thllt soils used for dry swales have infiltration rates of 0.27- 0.50 inches per hOIJr. TrapeZOidal or parabolic sha~recommended :( foot minimum, 6 foot maximum 3: 1 or flatter 1.0 % minimlJm, 6.0 % maximlJm 4.0 inches for water qualitY t.reatment 0.15 for waT.er quality t.reatment. (depth < 4" ) 0.15 - O. for depths betwl!l?n 4" and 12" 0.03 minimum for depth 12" 1.0 fps for w;:Jt.~r quality treatment. 5.0 fps for 2 year storm fps for 10 year storm length necessary for' 0 minute residence time The pollutant removal effectiveness of grllssed swales is summarized in Taple 4.3 Routine l'3ndsC3pe maintenance required. Rain Barrels Rain barrels are low;cost, effecTive, and easily main.tainable r.r::r.enr.ion devices applicable to both residential. and com.mer.cial/ industrial LID sites. Rai.n baT.Tel.s operar.e by rer:aini.ng a predetermined volume of rooftop runoff (i.e., r.hey prov1.de perrmment ~r.orage for a design volume); an overflow pipe provid.es som.e detention beyond the tetention capacity of the rain barrel. Figure 4-9 and Fi.gure 4-10 show Figll.T'P. 4.9. Typical rain borT'P.l II BBB Em .......sTIC R_ aAIlIu.I.S ~ I. RAIN BIIRftC. TO ec: KF.PT AT 11A1.F-FlLI.F.l) D4.iR1NG WI1'(IF.A OolONTHS to ~ $ARRSL r-R0l0I BRI;Al<INC ,r WATER .s ~ozr.1l . 4-78 " Low-Impact Developmenr Inregral'ed Management Practices ~~~,,_____~~__~""____"_~_'_'__"'~_~_~'_"""""_'_'__'_"'"_""""_~_~"'M'~'_'"_""~_"'~."""_"'_ .. .__>_.,..",.".,__~~__....." #1704 P.010/010 RESOURCES a typical rain. barrel. Ra.in ba.rre1s also can be used to score runoff for Iar.er reuse in. lawn and garden wat.ering De.ngn Con.~.5. Ra1.nwa.r.er iTom. any type of roofing ma.r.erial can be direcr.ed to rain barrels. To be aesr.heti.cally acceprJ.lbl.c, rain barrels can be J.ncorporar.ed Into the lor.'s I.and~ scapfng plan or pat.io or decldng design. Rain barrels pla.ced at each comer of me front si.de of rhe house should be J.andscaped for visual screening. GutteT.S and. downspouts are used toO convey wat.er from roofr.ops r.o rain barrels. Filcrati.on. screens should be used on gTJt.r.ers to prevent. clogging of debris. Rain barrels should also be equipped with a drain spigot that has garden hose threacllng, suitable for conn.ection to :3. drip ir.riga.tion syst.em. An overflow ourler. musr. be provided /;0 bypass runoff from large StomI. events. Rain banels must be designed with. removable, chHd~res1stan.r. covers and lllosquito screening on water entry boles. TIle size of the rain banel is a funcr:it.m. o( the rooftop surface area r:h.a.r. drains roO rh.e barre~ as well as rl1.e in.ches of rainfa/J t.o be stored. For example, one 4Z-gallon barrel provides 0.5 inch of runoff storage for a rooftop area. of approximately 133 square feet. Fi.g7l.re 4-10. Rain barrel applicati.orL 1.0 LID Cisterns Stol:m~ter runoff. cisterns a('e roof water m;m.agemenr devices cbs.!: provide retention sr.orage volume in underground storage ~(5. On~Ior. st.orage with. J,3.ter reuse of BtormW3ter also provides an. opportUnity for water c.onser.va.tion and dle posstbi1ir.y of reducing war.er u.dlir:y costs. Design. Considera.titms. Cisterns are applicable to resjdencia~ commercf.3l, and industri.al LID sites. Due to the size of roofr.ops and the am.01Jnt of impervi.olJsness of r.he drainage a,rea, increased runoff volum.e and peak discharge T.a.r.es for comm.ercial or industrial sites may require I.a.rger..capaci.ty cistems. Individual cistems can be located ben.eath each downspout, or sr.orage volum.e can be provided in one large, comm.on cj,~r.em. Preman.IJfa.ct.Urcd resid.ential use d.sr.ern.s come in sizes ranging from 100 t.o 1.,400 gaUons (Figure 4-11). Cisterns should be J.ocar.ed f()t ea.~ mainr:en:mce or replacem.enr:. Fig,-,T'P. -1,-11. Cistern. Imagl! Cou.r1:e.:ry of Pow Plastics, Ltd.., Devon, England Low-Impact Development Integrated Management Practices 4-19 "." J f . ~ . .... d'l Item. New Mail folder Page 1 of 2 Subject: Barr Engineering Q&E CC: "Fred Rozumalski" <frozumalski@barr.com> Date: Tue, 22 Jan 200214:37:11-0600 Status: Normal From: "Karen Kaul" <kkaul@barr.com> Return-Path: <kkE..1lI@barr. cqm> Received: from menin.isd.net (IDENT:root@menin.isd.net [208.153.200.22] (may be forged) ) by testi.isd.net (8.9.3/8.9.3) with ESMTP id OAA18855 for <aqontare@testi.isd.net>; Tue, 22 Jan 2002 14:38:28 -0600 Received: from gate.barr.com (gate.barr.com [209.98.63.2]) by menin.isd.net (8.9.3/8.9.3) with ESMTP id OAA02221 for <allison@isd.net>; Tue, 22 Jan 2002 14:38:02 -0600 Received: from prometheus.barr.com (prometheus.barr.com [172.25.33.25]) by gate.barr.com (8.10.2/8.10.2) with SMTP id gOMKbVp81222 for <allison@isd.net>; Tue, 22 Jan 2002 14:37:46 -0600 (CST) Received: from Barr#032#Domain#032#1-Message Server by prometheus.barr.com with Novell_GroupWise; Tue, 22 Jan 2002 14:37:19 -0600 Message-Id: <sc4d791f.020@prometheus.barr.com> X-Mailer: Novell GroupWise 5.5.4 Date: Tue, 22 Jan 2002 14:37:11 -0600 From: "Karen Kaul" <kkaul@barr.com> To: .~~J,Li.!!Ql!~i.p.g.,.n~ t >. Cc: "Fred Rozumalski" .<::.t.ro?1J!!lal~ki@b~J~:r. com> Subject: Barr Engineering Q&E Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="=_BBE6C76F.B7D6BC44" X-DPOP: DPOP Version 2.5g X-UIDL: 1011737059.001 Status: RO Fred Rozumalski asked me to send you the attached Q&E. I have provided it in a PDF format. Please let me know if you have any problems with the file. Karen Kaul Senior communications Specialist Barr Engineering Company h:.Js.?'1JL@ b~:rr .d:;.QI.!! 952-832-2931 g.e.,.~.di RJ View headers, C Variable width font, ~ Inline Images, C View as HTML [" Execute HTML .../ dmailweb.cgi?cmd=item&utoken=agontare@pop.isd.net_3a323344507527250101/22/2002 Clients Northland College Upper Swede Hollow Neighborhood Association Services Hydrologic analysis Site design and engineering Planting plans Community education programs Implementation supervision Deep-rooted plants facilitate infiltration. - BARR Rainwater Gardens A leader in ecologically sound stormwater management techniques, Barr has developed a unique expertise in rainwater gardens and other stormwater treatment practices. In designs like those pictured here, stormwater becomes a resource to be enjoyed rather than a nuisance to dispose of Constructed rainwater gardens are strategically placed to catch runoff from roads, parking lots, driveways, and roofs. Deep rooted plants are used to facilitate infiltration, absorb materials, and create bird and butterfly First year after planting habitat. Rainwater gardens can be used on small sites or as the main technique in a larger system, allowing a neighborhood, say, to forego expensive curb and gutter. The gardens are excellent for use in highly visible areas, where they not only manage runoff effectively, but add visual amenity. A neat edge and pedestrian access With a team of expert hydrologists, engineers, and landscape ecologists, Barr is ideally suited to design rainwater gardens that are both functional and beautiful. This rainwater garden serves as a neighborhood amenity. Client City of Marshall, Minnesota Funder The Legislative Commission on Minnesota Resources Services Site analysis Guided public focus groups Master planning ~~&'==- '__-"l"'~"", ---.. ':..__n~ Each lot is a sanctuary for birds and butterflies and allows for stormwater cleaning and infiltration. - BARR Ecological Neighborhood The city of Marshall has struggled with repeated flooding from the Redwood River. Funded by a research grant from the Legislative Commission on Minnesota Resources, Fred Rozumalski, with Professor Joan Nassauer of the University of Minnesota Department of Landscape Architecture, designed a residential neighborhood that would help ameliorate downstream flooding. Their approach was to take cues from the regionallandscape-once dotted with prairie pothole wetlands. In lieu of underground storm sewers, Rozumalski and Nassauer designed an above-ground drainage system and stormwater wetlands, to be built wherever possible on wetland soils. The design not only manages stormwater, but recreates lost wildlife habitat and provides residents with beautiful natural amenities. Rainwater garden Restored historic wetlands become an amenity within the ecological neighborhood. O"It.....__~~"'.I*tIll'*lIl~~~~ "Lakescaping for Wildlife and Water Quality" encourages property owners to plant a natural buffer zone between the lake and the lawn to reduce lakeshore erosion and increase wildlife habitat. Lakescaping Book Fred Rozumalski, of Barr Engineering, recently co-authored a book titled "Lakescaping for Wildlife and Water Quality," which promotes establishing native vegetation along lakeshores and reducing lawn size in order to protect water quality and create wildlife habitat. This DNR- sponsored book details the problems often faced by lake-property owners and offers an explanation of the lake ecosystem; how to solve lakeshore problems by creating a buffer zone; and detailed instructions on designing and planting lakeshore landscapes. Using his expertise in horticulture, landscape architecture, and ecology, Fred wrote the chapters on design, installation, maintenance, and exotic species control, and compiled the extensive plant lists. Native plants, such as this fireweed, are identified in the book as substitutes for invasive, non-native plants. This attractive and informative book can be purchased at Minnesota's Bookstore, 117 University Avenue, 8t. Paul, MN, or ordered by calling 1-800-657-3757 or 651-297-3000. Stage 1 Stage 2 Stage 3 Typicallakeshore sites transformed by lakescaping. This 3-stage design shows how a typicallakeshore property can be transformed from an open lawn to a site with an abundance of native vegetation that provides habitat in the form of a buffer zone between the lake and the lawn. The book offers several design options for a variety of lakeshore settings. - BARR Bibliographies Barr Engineering Company. 2001. Minnesota Urban Small Sites BMP Manual; Stormwater best management practices for cold climates. Metropolitan Council Environmental Services. Available from the Metropolitan Council at 651-602-1000 or www.metrocounci1.org. Claytor, Richard A. and Thomas R. Schueler. 1996. Design of Stormwater Filtering Systems. Chesapeake Research Consortium. Available from The Center for Watershed Protection at 410-461-8323 or www.cwP.org. Henderson, Carrol. 1999. Lakescaping for Wildlife and Water Quality. Minnesota Department of Natural Resources. Available from the St. Paul Minnesota's Bookstore. Minnesota Pollution Control Agency. 2000. Protecting Water Quality in Urban Areas; Best management practices for dealing with storm water runoff from urban, suburban and developing areas in Minnesota. Minnesota Pollution Control Agency. Available from the MPCA, contact Mary Osborn at 651-296-7523 or www.pca.state.mn.us/water/pubs/sw-bmpmanual.pdf Allison, The bibliography above is a few references that I had put together for another project. All of them have great information on how to develop and use alternative methods to improve stormwater quality and decrease the quantity and flow rate. I hope that a list of references will help you. Below is a diagram that I use in describing what actually happens with development and urbanization. We promote the use of these alternatives to mimic natural conditions and ecological development as much as possible. So, the use of rain barrels to trap water and rainwater gardens to infiltrate water and to evapo-transpire back to the atmosphere are ways to remediate for the excess stormwater. The final thought on an argument is that new construction always creates more runoff problems then can be mitigated for. I hope this helps. If you need to call me, I will be here for another half hour or so (4:45 pm). Otherwise my home phone number is 952-854-2990 and will be home by 5:45 pm. Rusty Schmidt Landscape Ecologist URS / BRW, Inc 700 Third Street South Minneapolis, MN 55415 612-373-6828 FAX: 612-370-1378 rusty_schmidt@urscorp.com