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Design Criteria & Standards for a Wetland/Floodplain Administrative Permit

Compliance with the design criteria and standards, as determined by the director, shall be required for a minor project to be considered for approval by an administrative permit and may be required for other use permits by the entity with final approval authority in the absence of a demonstration by the applicant that compliance with a particular design criteria or standard is not feasible and prudent or is not necessary to assure that the operation will cause the least possible damage and encroachment or interference with natural resources and natural processes within the watercourse and wetland areas in the township.

 

(1)  The mitigation area is 0.5 acres or less in size and is to be on the same site as the proposed operation for which a permit is required.  Off-site mitigation may not be approved by an administrative permit.

(2)  The minimum area or volume and location requirements for mitigation are as follows:

  • In an environmental features setback area, the mitigation area shall be at least as large as the area of disturbance (1:1 mitigation ratio).
  • The mitigation volume of material to be removed from the floodplain shall be at least a large as the volume of fill (1:1 mitigation ratio) and the mitigation area shall be directly connected to the floodplain impacted.
  • For operations in a wetland, the mitigation area shall be at least twice as large as the area of disturbance.
  • If providing the wetland mitigation area required by subsection (c) is not feasible, the largest feasible mitigation area that is at least as large as the area of disturbance may be approved if there is an enhancement that increases the number of plant species in the wetland by 30, with the new plant species to be planted required to be native/indigenous plants in accordance with the wetland/environmental mitigation manual.

(3) Plans for mitigation are required and shall include all of the following:

  • A description of the topography, soils, hydrology, and vegetation.  Soil boring information and groundwater monitoring data should supplement this description.
  • The acreage to be restored, created, or preserved by ecological type
  • Cut and fill volumes
  • A description of the functions provided by the wetlands to be impacted and the proposed mitigation wetlands.
  • Water budget of inputs and outputs to the proposed mitigation wetland (e.g., precipitation, groundwater, runoff, evapotranspiration).
  • Existing Conditions Plan that includes topographic information (1 or 2 foot contour intervals), roads, trails, structures, property lines, directional arrows, scale, and the exact size and boundaries of existing environmental features setback, wetlands, streams, and 100-year floodplain.
  • Wetland Mitigation Plan that includes:
    1. A description of the sources of hydrology, the source and type of soil amendments, wetland vegetation establishment, and wildlife structures.
    2. A plan view showing all of the proposed conditions of the mitigation site including all contour elevations (at 1 foot contour intervals), structures, the type and size of all proposed wetland areas, property lines, directional arrows, scale, the conservation easement area, and the proposed method of demarking the environmental features setback.
    3. Cross-sections showing the existing and proposed grades.
  • Landscape Plan which includes a plan view, installation methods, planting list that specifies plant type, species list with scientific and common names, size, and quantity as well as distribution within the mitigation areas in accordance with the wetland/environmental mitigation manual.
  • Schedule and Construction Methods: A schedule and methods for completion of the mitigation site must be provided (e.g., initiation, planting, completion). The site preparation and soil erosion/sedimentation control methods to be used during construction should be described.
  • Long-term Protection Plan: A preservation notice and an accompanying recordable size site plan showing the wetland, environmental features setback area, and 100-year floodplain must be provided.

(4) Only native/indigenous trees, shrubs, grasses, sedges, forbs, vines and other herbaceous plants approved by the director pursuant to the wetland/environmental mitigation manual, may be planted in floodplains, floodways, wetlands, watercourses, woodlands/woodland preservation areas and environmental features setback areas.

(5) The location of structures (permanent or temporary) is not allowed within recorded and/or township established preservation areas or easements.

(6) No direct discharge of storm water, sump water or wastewater is permitted to wetlands, watercourses, woodlands/woodland preservation areas and environmental features setback areas.

(7) Seawalls must meet the following design standards:

  • Any type must be installed at or above the ordinary high water mark of a watercourse.
  • Existing vertical and horizontal contours of the shoreline shall be maintained.
  • Vertical seawalls (steel or vinyl) are not permitted where vertical walls do not currently exist.
  • Boulder seawalls will be installed on a 1:1 slope (45 degree angle), approved geotextile fabric shall be installed behind the proposed seawall, and approved stone backfill shall be used to provide adequate drainage.
  • Four (4) to eight (8) inch diameter natural cobblestone must be placed (minimum width of twelve (12) inches) at the toe of the entire length of the seawall.

(8) Impervious surfaces within an environmental features setback area must be constructed such that runoff is directed away from watercourses and wetlands or to a native plant area to provide the maximum infiltration as possible.

(9) Impervious surfaces can not exceed 25% of an environmental features setback area and shall be constructed in a way to increase infiltration of storm water.

(10) Trees within the environmental features setback can be trimmed to a height of 12 feet and herbaceous and/or shrubs can be cut to a minimum height of 4 feet for the creation of a viewshed.

(11) Beach sanding must meet the following design standards:

  • The purpose of the fill is for the creation, improvement, or restoration of swimming areas and beaches.
  • The fill is placed above the ordinary high water mark.
  • The fill is 10 cubic yards or less and is completed as one complete project.
  • The material is from a source approved by the director and is clean, nonpolluting, free from debris, organic materials, and waste metal products.
  • The total area filled should not exceed 25% of the environmental features setback.

(12) Driveways must meet the following design standards:

  • Any upland on the property or other alternatives, such as obtaining a permanent easement for access from adjacent upland if available or a shared driveway shall be utilized to the greatest degree possible.
  • The location of the driveway is at the least damaging place on the property and creates the minimum wetland impact.
  • The portion of the driveway in the wetland can have a maximum base width of 16 feet and paved width of 12 feet. The maximum length of the driveway is 50 feet.
  • No ditches may be placed in the wetland in association with the driveway.
  • The driveway must terminate at a buildable upland site.