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I I I I I I I I I I I I I I I I I I I NOTE: An ordinary high water mark has not been set by the Department of Natural Resources or Ramsey County. The record high lake elevation was 881.27 In t978 during construction of an Improved outlet structure. Since the structure was constructed, many lakes In the area have reached thel r al I -tl me high. Between 1981 and 1986, the reg Ion h as gone through the wettest 2-year, 3-year, 4-year and 5-year precipitation cycles on record, according to the State Climatologist. After checkl ng with the noted agencl es, a high water mark was set based on the highest elevation reached since t978 of 878.25. This el evatl on w I II be used I n the Stormwater Management PI an and w I II be reviewed by the Rice Creek Watershed District. A 75 foot construction setback Is assumed to begin at this elevation. A. .s!.Qrm~~.!~.L.MgDag~m1!D!_fl~D_Bgq.ul.ri!ID.eDt~ A permit Is required from the Rice Creek Watershed District for this project. A Stormwater Management Plan for this site must address stormwater management for al I contiguous properties owned by the applicant, and must be prepared prior to PUD Appllcati on. Necessary information and exhibits that must accompany a permit appl icatlon for approval of a Stormwater Management Plan Include the following: 1. Identi f Icatlon of adjacent I ands over which the applicant has ownership or Jurisdiction. 2. Del ineatlon of areas contributing runoff to the site. 3. Design details showing the stormwater runoff rate from the developed site does not exceed the runoff rate of the site In an undeveloped condition for both a 1-year and 100-year return frequency rainfall event. 4. Determination of the normal, 1-year and tOO-year water elevations for stormwater retention areas. 5. Storage volume determination and detention site contours and/or cross sections. 6. Floodplain, shoreland and/or wetlands del ineation. 7. Outlet structure details with dimensions and elevations related to MSl datum. 8. Details of any structureCs) that will provide floatable trash removal and 01 I recovery capabl I It I es to treat runoff from 1-year ralnfal I event. 9. Description of surface and subsurface soils. 10. AI I supportive hydrologic computations. -14- 8621