Are you sure you don’t need a NPDES permit?

Construction site owners and operators must apply for an NPDES/SDS construction stormwater permit from the MPCA for any construction activity disturbing:

• One acre or more of soil, or
• Less than one acre of soil but the activity is part of a larger common plan of development or sale that is greater than one acre.

A common plan of development or sale is a contiguous area where multiple separate land-disturbing activities may happen at different times, on different schedules, but under one proposed plan.

Examples include:

• Residential subdivisions
• Phased projects
• Industrial parks

If you are building on one lot within a larger subdivision over an acre, you still need an NPDES/SDS permit.

REMINDER

MS4 Permittees (cities, counties, townships) must provide written notification to owners and operators proposing construction activity, including projects less than one acre that are part of a larger common plan of development or sale, of the need to apply for and obtain coverage under Minnesota’s Construction Stormwater (CSW) Permit (MS4 Permit Item 19.6).

In addition, MS4 Permittees must implement and enforce a Construction Site Stormwater Runoff Control and Post-Construction Stormwater Management program to address construction activity with land disturbance of greater than or equal to one acre, including projects less than one acre that are part of a larger common plan of development or sale, within the permittee's jurisdiction and that discharge to the permittee's MS4… (MS4 Permit Items 19.2, 19.3, 20.2 and 20.3).

For more information, visit the MPCA website at www.pca.state.mn.us/water/construction-stormwater or call the MPCA at 651-296-6300 or 800-657-3864.