RUNOFF RATING

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					    RUNOFF RATING WORKSHEET                          (VERSION 2.1)

                                                             ENTER LOT SIZE** ------------------------------                 SQUARE FEET


    PERVIOUS AREAS                                                                                                           Land Use Numbers for Hydrologic Soil Type
           OPEN SPACE - LAWNS, PARKS, GOLF COURSES, ETC.                                                                               A             B               C            D
            Poor condition; grass cover < 50%                                                                                          .             .79 ----------- .86 -----------
                                                                                                                             -----------68 -----------                            .89
            Fair condition; grass cover 50% to 75%                                                                                     .             .69 ----------- .79 -----------
                                                                                                                             -----------49 -----------                            .84
            Good condition; grass cover > 75%                                                                                          .             .61 ----------- .74 -----------
                                                                                                                             -----------39 -----------                            .80
           SHRUB/GRASS/SEDGE COMMUNITY - MIXTURE OF DEEP-ROOTED NATIVE PLANTS
            Poor condition; cover < 50%; no mowing                                                                                     .             .67 ----------- .77 -----------
                                                                                                                             -----------48 -----------                            .83
            Fair condition; cover 50% to 75%; no mowing                                                                                .             .56 ----------- .70 -----------
                                                                                                                             -----------35 -----------                            .77
            Good condition; cover > 75%; no mowing                                                                                     .             .48 ----------- .65 -----------
                                                                                                                             -----------30 -----------                            .73
           WOODS - GROUND COVER PRIMARILY NATIVE PERENNIALS AND/OR FOREST LITTER*
            Poor condition; small trees, brush, and forest litter removed (cover < 50%)                                                .             .66 ----------- .77 -----------
                                                                                                                             -----------45 -----------                            .83
            Fair condition; small trees, brush, forest litter present; not covering soil (cover 50% to 75%)                            .             .60 ----------- .73 -----------
                                                                                                                             -----------36 -----------                            .79
            Good condition; small trees, brush, and forest litter completely covers soil (cover > 75%)                                 .             .55 ----------- .70 -----------
                                                                                                                             -----------30 -----------                            .77
    IMPERVIOUS AREAS
            Roofs, paved driveways, paved walkways, paved patios, etc.                                                                 .             .98 ----------- .98 -----------
                                                                                                                             -----------98 -----------                            .98
            Gravel driveways, gravel walkways, etc.                                                                                    .             .85 ----------- .89 -----------
                                                                                                                             -----------76 -----------                            .99
                         YOU MUST ACCOUNT FOR THE SQUARE FOOTAGE OF THE ENTIRE LOT
                                                                                                                                   0            0               0             0

                                                                                                                                       Total Area               0

                                                                                                                                       Runoff Rating            0

    POINT CREDITS:
           PLACE AN "X" IN THE BOX IF YOU CAN TAKE CREDIT FOR A SEWER SYSTEM                                                                -----
           (IE WAPOGASSET, BEAR TRAP, AND MAGNOR LAKES HAVE SEWER SYSTEMS)
           (1 POINT CREDIT)

              PLACE AN "X" IN THE BOX IF YOU HAVE ESTABLISHED CONTINUOUS VEGETATIVE COVER                                                   -----
                  ON THE LAKESHORE - DEFINED AS FOLLOWS:
              A vegetated buffer strip (shrub/grass/sedge community) of land 35 feet wide measured perpendicular from
                the ordinary high water mark (OHWM), where the viewing corridor does not exceed 30 feet measured
               parallel to the shore. (1.5 POINT CREDIT)

                                                                                            ------------------------------


    MITIGATION OPTIONS:
   SHRUB/GRASS/SEDGE COMMUNITY VEGETATION***                      Area to Plant:                                        0 Square Feet

                              RAIN BASINS (4 IN. DEPTH)***                  Area:                                       0 Square Feet

                                 RUNOFF DETAINMENT ***                  Volume:                                         0 Cubic Feet


    * Woods - Stand that consists of one or more tree species with an understory of shrubs
        and immature trees. Ground cover consists primarily of native perennials. The ratio
        of shrubs to mature trees is 1.5:1 or greater. Typical species composition and
        structure are described in The Vegetation of Wisconsin, Curtis, for both northern
        and southern forests.
    ** Lot size shall only include area of property within 300' of Ordinary High Water Mark, OHWM (measured perpendicular from OHWM).
    *** Obtain specific requirements from the Polk County Zoning Department




RUNOFF RATING (Version 2.0)                                                                                                                                 4/5/2010   10:51 AM
HELP
  RUNOFF RATING          (VERSION 2.0)

  The runoff rating is a process used by the Polk County Shoreland Protection Zoning Ordinance to reduce the
  effects of development (particularly impervious surfaces) on water quality. The goal runoff rating has been
  determined to be 69. The goal runoff rating is based on a typical lot that allows for development
  while maintaining some of the necessary land cover types and/or runoff controls to protect water quality.
  The runoff rating is determined for the entire lot up to 300' measured perpendicular from the ordinary
   high water mark (OHWM)).

  To complete the rating the following items need to be completed:
  1. Measure each land cover type on the lot and draw them to scale. (Measure up to 300' perpendicular from the
      OHWM, if the lot extends that far, ignore any of the lot beyond 300').
      ENTER LOT SIZE (square feet). (Up to 300' perpendicular from the OHWM.)
      Convert the land cover types into areas (square feet).
      INCLUDE "NEW" (NOT YET BUILT) IMPERVIOUS AREAS.
  2. Determine the Hydrologic Soil Type from the HYDROLOGIC SOIL TYPE MAP (click the adjacent button)
      or contact the Polk County Zoning Department.
  3. Place the appropriate amount of area (square feet) for each land cover types into the worksheet
      under the appropriate Hydrologic Soil Group. This is where -------- is shown.
           a. Refer to LAND COVER TYPE PHOTOS for an explanation of the different land cover types.




  4.    The program will determine the Runoff Rating for the lot. MAKE TO ACCOUNT FOR THE
         LAND COVER TYPES FOR THE ENTIRE LOT.
  5.    If the Runoff Rating for the lot is less than or equal to the goal of 69, no mitigation is needed.
  6.    Place an "X' in the boxes for POINT CREDITS:
                        a. One point credit will be applied for the lots with public sewer systems, and/or a
                        b. One and a half point credit for landowners who establish continuous
                            vegetative cover (shrub/grass/sedge community) starting from the OHWM
                            and continuing landward.
  7.    If the rating has been reduced to 69 or less by Point Credits, no mitigation is needed.
  8.   MITIGATION OPTIONS. Click mouse pointer on "CALCULATE" to obtain the amount of
        vegetation to plant, size of rain basin, and amount of water to detain. Any one of these
       can be used for mitigation.
  9.   More specific information shall be obtained from the Polk County Zoning Department
       regarding mitigation.
dicular from the