Laserfiche WebLink
CONSENT ITEM — 8N <br />,—ARZEN HILLS <br />IU l flu [o] MR011110LVA <br />DATE: April 8, 2024 <br />TO: Honorable Mayor and City Councilmembers <br />Dave Perrault, City Administrator <br />FROM: David Swearingen, P.E. Public Works Director / City Engineer <br />SUBJECT: Grant Agreement with Rice Creek Watershed District for the 2024 PMP <br />Budgeted Amount: Actual Amount: Funding Source: <br />$70,000 $70,000 (City) Stormwater Utility Fund, <br />$70,000 (RCWD) RCWD Stormwater Grant <br />Council Should Consider <br />Motions to approve, table, or deny the following: <br />• 2024 Stormwater Management Grant Agreement with the Rice Creek Watershed <br />District for the 2024 PMP Street & Utility Improvements Project in the amount of <br />$70,000. <br />Background/Discussion <br />On December 21, 2023, City staff applied for the 2024 Stormwater Management Grant Program <br />provided by the Rice Creek Watershed District to support funding the stormwater quality <br />structures included in the 2024 PMP Street & Utility Improvement project. These structures will <br />ultimately improve the water quality that drains towards Valentine Lake and will help the City <br />achieve its goals to meet the Total Maximum Daily Load (TMDL) for that water body. <br />The structures are referred to as, SAFL Baffles, which are a pretreatment BMP that capture and <br />retain stormwater sediment total suspended solids (TSS). The MnDNR indicates they provide <br />considerable water quality benefits. SHSAM (Sizing Hydrodynamic Separators and Manholes) <br />software was used to estimate the percent removal of suspended sediments in the stormwater <br />runoff from SAFL Baffles in sump storm structures. Using the catchment areas that drain to each <br />storm sewer system that will have a SAFL Baffle installed throughout the project along with the <br />results from SHSAM, the total pollutant reductions were determined using MIDS modeling. The <br />Total Phosphorus loading is 30.67 lbs. and the removal amount is 7.05 lbs. for an overall <br />removal of 23% TP. The Total Suspended Sediment loading is 5,571 lbs. and the removal <br />amount is 2,338 lbs. for an overall removal of 42% TSS. <br />Page 1 of 2 <br />