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features in heu of raingardens if there was difficulty incorporating the required amount of storage volume within surface features in specifIC areas. Example 2 - Fridlev. This neighborhood street reconstruction is scheduled for reconstruction this year and the District is currently assisting the city with design and implementation of a large- scale raingarden / infiltration basin in Jay Park as well as several smaller scale raingardens behind the curb on residential lots. The area directly tributary to the 1.0 miles of roadway to be reconstructed is approximately 26.5 acres. Soils borings indicate predominantly sandy soils with no groundwater encountered. In order to meet the proposed 0.8-inch rainfall event standard, 13 rain gardens with a total length of 760 feet and an average width of IS-feet, 180 linear feet of infiltration trench, 4 sump catch basins and a 5,000 square foot infiltration basin were incorporated. Additional opportunity for incorporation of BMPs along the roadway is possible, however, there was a concerted effort to avoid the south and west side of the roadway, where a natural gas line was recently rcconstructed. Example 3 - Mounds View. This residential street reconstruction project was originally scheduled for this year, but postponed due to resident concerns. The District has worked with city staff and consultants to identify several BMPs along the project corridor and these have been incorporated into the City's feasibility study for the project. These features with the addition of a few others have been incorporated to meet the 0.8-inch event standard. The area directly tributary to the 1.4 miles of roadway to be reconstructed is approximately 51.5 acres. Soils are predominantly sandy with no apparent groundwater concerns along the road right-of-way. In order to meet the proposed 0.8-inch rainfall event standard, 3 rain gardens, 100 linear feet of french drains, 370 linear feet of infiltration trenches, 2 infiltration basins totaling 8,800 SF, 2 biofiltration basins totaling 2,300 SF and 4 sump catch basins providing pretreatment for the trenches were incorporated. Example 4 - Arden Hills. This neighborhood street reconstruction project is scheduled for reconstruction in 2006. The City of Arden Hills is cunently investigating regional treatment ponding in adjacent wetland areas to satisfy the District's cunent NURP standard. This project was assessed in light of the proposed 0.8-inch rainfall standard and an attempt was made to meet the proposed lUle without the use of existing wetland areas. The neighborhood is heavily wooded with rolling topography and average lot size of Y, acre. The area directly tributary to the 1.2 miles ofroadway to be reconstructed is approximately 22 acres. For this example it was assumed that the soils had low iniiltration potential and most features would require an under-drain discharging to the storms ewer. Future soil boring may demonstrate that infiltration is feasible, thus allO\ving for infiltration as apposed to filtration ofthe runoff. Thirty-six locations for potential small seale BMPs were identified in the field. In order to meet the proposed 0.8-inch rainfall event star1dard, twenty-five of tl1ese locations were utilized. Twenty-one rain gar-dens with a total length of 900 feet and an average width of 10-feet were incorporated. Five biofiltration basins with an average surface area of 600 square feet were also incorporated. In most cases there is room to increase tl1e size of tl1e proposed biofiltration basins Ermnons & Olivier Resources, Inc. Page 6 of7