Waukesha County

Storm Water Management & Erosion Control Permits


WHEN: Proposed land development activity in unincorporated areas that will expose soil to erosion (grading or filling) or increase storm water runoff (add rooftops & pavement) and meets any of the following permit thresholds:

  • 3,000 square feet land disturbance (grading/structures)
  • 400 cubic yards of excavation, fill or a combination of these
  • 300 lineal ft. of new utility or other open channel disturbance (unless utility is plowed in outside of ditch line)
  • All new “subdivisions” (as defined by local codes)
  • All new public or private road construction
  • All sites where at least ½ acre of impervious surface is added to the landscape (rooftops, pavement, etc.)
  • Other sites, regardless of size that the LRD determines is likely to cause an adverse impact to an environmentally sensitive area or other property (may require erosion control and/or storm water mgt. plan)

WHY: To minimize water pollution, flooding, and other negative impacts of urbanization on downstream water resources (lakes, streams, wetlands & groundwater) and property owners. Aimed to control soil erosion and sedimentation during construction and manage the discharge of storm water after development. Pursuant to Waukesha County Code Chapter 14 – Article VIII – Storm Water Management and Erosion Control.

WHO: The Waukesha County Department of Parks and Land Use - Land Resources Division issues permits.

HOW: To obtain a permit, the applicant must prepare erosion control and/or storm water management plans, as noted above. The contents of these plans depend on the size and complexity of the site. For erosion control plans on sites one acre or less, a short checklist of plan requirements is on the application form. For all storm water management plans and erosion control plans for larger sites, published checklists and other technical guidelines are available. A submittal must include the following documents (available here):

  • Signed Application (including a list of project contacts)
  • Permit Fee
  • Site Map (see checklist 1)
  • Erosion Control Plan (preliminary or final – see checklist 2)
  • Storm Water Management Plan (preliminary or final – see checklist 3)
  • Narrative/support materials explaining plan contents & designs, construction sequence, etc.
  • Other applicable items, such as a storm water facility Maintenance Agreement or Performance Bond

New land divisions that meet any of the triggers listed above for storm water management plans are required to obtain a Preliminary Review Letter prior to asking for action on a preliminary plat or other zoning approvals. Obtaining conceptual/general review comments on these plans will help facilitate other plan review and approval processes. It also allows the applicant to proceed through those processes without committing the resources needed to complete final engineering designs and construction plans or line up contractors, which are all needed to obtain a permit. Certification of compliance (see checklist 4) with this ordinance is also required before recording new land divisions at the Waukesha County Register of Deeds.


An appeal of a decision by Land Resources staff must be made in writing and submitted to the Board of Adjustment within 20 days of the date of decision. (Staff will assist you.)


  • Staff must approve or deny applications within:
  • 10 working days of submittal/resubmittal for sites that disturb 1 acre or less; or
  • 20 working days of submittal/resubmittal for sites that disturb greater than 1 acre.


Other permits from local, state or federal agencies may also be required. See Coordinating Agencies.

Business Hours: 8:00 am - 4:30 pm Monday - Friday (excluding holidays)
515 W. Moreland Blvd., Waukesha, WI 53188

Room AC 170 - (262) 896-8270 - Land Information System
Room AC 230 - (262) 548-7790 - Park System, Planning and Zoning
Room AC 260 - (262) 896-8300 - Environmental Health, Land Conservation and Recycling
Room AC 320 - (262) 548-7920 - Community Development

If you have questions, please email Department of Parks & Land Use or call the numbers listed above.

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