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f. Comprehensive Development Plan Stormwater Management The first phase stormwater management plan was developed by Schreiber Anderson (SM) in 2001. The current Novation Campus " phase is being developed by JSD Professional Services, Inc. The following information and watershed Exhibit C-0.2 (see exhibit section) have been prepared by JSD. The detention area for the phase one 27 -acre parcel, as proposed and approved, required 1.8 acre-feet of storage to meet applicable Dane County standards. Based upon the provided Drainage Basins, three watersheds were used. Two watersheds, Area 1 and Area 2, drained into two separate basins. A third watershed, Area 3, discharged offsite and undetained into the Lake George Drive storm sewer. The smaller detention basin is located at the corner of Badger Road and Rimrock Road and has a storage capacity of 0.3 acre-feet. The larger basin, and the one we would like to utilize, was designed to be 1.5 acre-feet. The larger basins watershed was designed to be 18.2 acres, or 64 percent of the total drainage area of the development. However, the designed 1.5 acre-feet pond is 83 percent of the total required pond volume (1.8 acre-feet) allocated to detention. Therefore, the pond was overdesigned for the development. Additionally, a conserva- tive estimate of the current storage capacity, based upon current survey data, indicate a storage volume of approximately 2.3 acre-feet. This will meet and exceed the Dane County requirements as ouftined in Chapter 14. The majority of the Novation Technology Campus which is now part of the Novation Campus II plat will become part of the Lake George watershed. A portion of the east side of the original plat area and the lot containing the existing strip retail and storage buildings, located south of the pond on Rimrock Road, does not have the grade change to convey stormwater runoff to Lake George. These areas currenfty drain into the storm sewer system in Lake George Drive and offsite without any detention or TSS reduction. The adjustment of the original stormwater plan adjusts the drainage of this area to take advantage of proximity to lake George. Please refer to the table below for a summary of the areas. Area A 419,425 s.f. (9.63 acres) Area B 110,840 sJ (2.54 acres) Area C 206,652 s.f. (4.74 acres) Total New Area Proposed to Drain to Existing Detention Area 317,492 s.f. (7.29 acres) This will be a total decrease (101,933 sf) in area draining to the pond from the design value. Additionally, the existing re-development of the strip retail and storage buildings will receive full treatment of runoff rate control and total suspended solids within the pond rather than just the redevelopment standards. The current water elevation of Lake George is at 14.5. At proposed build-out, the estimated 100-year water elevation will be 18.0. Surface techniques of managing stormwater run-off will be encouraged, particularly where impervious surfaces are present. Pervious surfaces not only allow run-off to be managed on site, but with the incorporation of such elements as green roofs can help insulate buildings and reduce heat transfer. Lighter color pavements, including grassy pavers and porous pavements also reduce the amount of heat transfer in parking lots, giving a better environment for plant grow1h and cooling adjacent outdoor spaces. Due to the brownfleld history of the site, filtration and use of previous surfaces will be limited in certain specific areas. III