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HomeMy WebLinkAbout8B - Stormwater Grant Opportunity MEETING DATE: AGENDA #: PREPARED BY: AGENDA ITEM: PRESENTATION: JANUARY 4, 2010 88 Ross Bintner, Water Resources Engineer PRESENTATION OF sTORMWATER TREATMENT GRANT OPPORTUNITY The City of Prior Lake manages its stormwater treatment system to continually improve pollutant removal efficiency. Water quality ponds are the single largest ongoing investment in the treatment system, their improved function can have an immediate effect on the quality of our lakes, wetlands and streams. The City is currently cleaning and retrofitting 6 of the 135 total treatment ponds to removed accumulated sediment, restore and enhance their planned treatment effectiveness, and meet increasingly strict water quality requirements. Staff has recognized a potential new method to increase system efficiency and test this innovate treatment method as part of the 2009 Water Quality Pond Maintenance (City project 09-013), currently under construction. By taking advantage of a project already in place, a new method of treatment can be tested at relatively low cost, potentially leading to further state, and national investment in, and study of, the Prior Lake water quality treatment system. Staff is not proposing any action as part of this presentation, but will ask the City Council if it wishes to direct the staff to prepare a grant application to the Scott Watershed Management Organization and Prior Lake Spring Lake Watershed District pursue this opportunity. www.cityofpriorlake.com c~IwI).~!~~tfk~-~}9~QPt ir,lclf~ 9,R~,;;lfElA245 RIO/, , %: t....~~.... u~a, ~JNNESo1" ' STORMWATER TREATMENT IJill'GRANT PRESENTATION \) ESO~' 2030 VISION-NATURAL R10-l1 RESOURCES FIVE-YEAR GOAL: Implement plans to monitor and improve surface water quality (i.e. lakes, ponds, wetlands, streams, storm water runoff and non-point runoff) in accordance with the Local Surface Water Management Plan. ~ r ~\ ESO . WATER QUALITY STANDARDS RIO~:.ALWAYS CHANGING ~ 1990 ~~i~~T~~1E~SACCJA~~TJ~~~INATlON SYSTEM (NPDES) PHASE I 2004 MINNESOTA PHOSPHORUS FERTILIZER BAN 2005 CLEAN WATER ACT NPDES PHASE II 2005 NON-POINT FOCUS SHIFTS TO POLLUTION PREVENTION AT THE SOURCE 2010 UPPER PRIOR/SPRING LAKE TOTAL MAXIMUM DAILY LOAD (TMDL) 2011 THIRD GENERATION NPDES MS4 PERMIT ...." 1"'" ESO~\ RECENT STORMWA TER RIO '.' GRANTS , A" "Ii . 2008 NEIGHBORHOOD RAINGARDENS . GRAINWOOD BIO-RETENTION BASIN .' . SWEEPING PROGRAM GRANT E! SO~ \" . COUNTY ROAD 12 BIO-RETENTION AND INFILTRATION GRANT RUNOFF MANAGEMENT TREATMENT TRAIN . SAND IRON FILTER GRANT RIO... OPPORTUNITY '4.. . CITY CURRENTLY CLEANING AND RETROFITTING 6 OF 135 PONDS . INNOVATIVE SAND/IRON FILTER . USE POND PROJECT ALREADY BID TOWARD LARGER GRANT OPPORTUNITIES AND STUDY . COST TO ADD IRON TO THE FILTER BENCH LOW COMPARED TO GRANT POTENTIAL . GRANT COMING TOGETHER QUICKLY - OTHER CITY PARTNERS SUPPORT PROPOSAL . WANT CITY COUNCIL DIRECTION BEFORE OFFICIALLY SOLICITING PARTNERS ~ .......... O~\; ES WHAT IS AN IRON SAND FILTER RI &ND HOW DOES IT WORK? '4. SAND FILTER ALREADY PLANNED - IRON ADDED AND MIXED WITH SAND . DISSOLVED PHOSPHORUS REACTS AND BINDS TO IRON PARTICLES . REMOVING DISSOLVED PHOSPHORUS WITHIN THE TREATMENT PONDS REDUCES ESO'\ PHOSPHORUS TO DOWNSTREAM LAKES AND STREAMS c;")l 2. l: ~ .../"'>'..---7'~~ $ "3 '''. 2- ""''''-~''"'~--,...,.""",~ /A~ SAND IRON FILTER BENEFITS RI 0 ~.lABORATORY TESTS SHOW PROMISING DISSOLVED t PHOSPHORUS REMOVAL RATES SMALL INITIAL INVESTMENT NOW COULD INITIATE LARGE STATE AND FEDERAL STUDY DOLLARS . IF THIS CONCEPT IS SUCCESSFUL IN THE FIELD, THE SAND IRON FILTER COULD BECOME ANOTHER PRACTICE THAT CAN BE USED TO MEET FUTURE . TMDL STANDARDS ..,:i:icc::<':VFUTURE LOW COST BMP-SAND IRON FILTER CAN BE RETROFITTED INTO ALREADY CONSTRUCTED PONDS FOR A RELATIVELY LOW COST IF COMBINED \7.. WITH REGULAR POND MAINTENANCE ESO"\ v ANNUAL POLLUTANT RI O~EDUCTION LIABILITY ~...C . ASSUMING TMDL STANDARD PHOSPHORUS LOADING RATE OF 5,000 POUNDSNEAR . SAND IRON FILTER COULD LOWER AVERAGE POND TREATMENT RATES FROM $440 PER POUND OF PHOSPHORUS TO $410- \$260 PER POUND OF PHOSPHORUS --"vTHIS RESULTS IN A MINIMUM LONG TERM ~ POLLUTANT REDUCTION LIABILITY :-\ ~.SAVlNGS OF $150,000 WHICH COULD ESO . INCREASE SUBSTANTIALLY DEPENDING ON THE FILTER PERFORMANCE COST TO PURSUE GRANT RIO: ~ . CITY STAFF TIME INVESTMENT OF APPROXIMATELY 40 HOURS . $7,000 INCREASE TO POND MAINTENANCE PROJECT (SUCCESSFUL GRANT FROM WATERSHED DISTRICT AND SCOTT WATER MANAGEMENT ORGANIZATION TO COVER THIS COST) ~' ~~: ESO RIO, -.tfj '+'il"}':">>>>'-,:: ' ...",w 'i"._,..."..... " <<h ESO~\ RI04 .,,' ESO'\ \" NEXT STEPS WITH CITY COUNCIL DIRECTION, CITY STAFF WOULD PURSUE GRANT WITH WATERSHED DISTRICT AND SCOTT WATER MANAGEMENT ORGANIZATION IF GRANT IS APPROVED, IRON WOULD BE ADDED TO THE SAND FILTER ON TWO PONDS IN LATE JANUARY OR EARLY FEBRUARY SAMPLING AND TESTING OF SAND I IRON FILTERS IN MAY IN JUNE, CITY, WATERSHED DISTRICT, WATER MANAGEMENT ORGANIZATION AND UNIVERSITY OF MINNESOTA APPLY FOR SIGNIFICANT STATE AND FEDERAL GRANT DOLLARS FOR STUDY OF THE SANDIIRON FILTER QUESTIONS?