The Construction Stormwater General Permit (CSGP) requires the development of a Construction Plan. An integral part of the Construction Plan includes a stormwater Pollution Prevention Plan. The Stormwater Pollution Prevention Plan (SWP3) addresses several issues. First, the plan outlines how erosion and sedimentation will be controlled on the project site to minimize the discharge of sediment off-site or to a water of the state. Second the plan addresses other pollutants that may be associated with construction activity. This may include disposal of building materials, management of fueling operations, etc. Finally, the plan should also address pollutants that will be associated with the post-construction land use.
The Construction Plan requirements can be found in Section 4.1 of the CSGP. The plan is divided into several parts that includes basic resource information, an existing project site layout, a grading plan, a drainage plan, and the SWP3.
The CSGP requires that the Construction/SWP3 is submitted for review prior for review. The plans must be submitted in accordance with the CSGP and to the designated plan review entity. This may include a local Municipal Separate Storm Sewer System (MS4), a local Soil and Water Conservation District (SWCD), or the Indiana Department of Environmental Management (IDEM) Stormwater Program.
IDEM has developed a guidance document that is an outline of items that are required to be contained in a Construction Plan. This document is the same format and is laid out similar to the plan review form that will be used by IDEM and SWCDs reviewing plans on behalf of IDEM. In addition, each plan element includes the expectation for each plan element. The items within this document have been divided into three distinct categories, including:
- General Plan Components
- Stormwater Pollution Prevention Plan – Construction Component
- Stormwater Pollution Prevention Plan – Post-construction Component.
Each item is identified with a letter and number that can be directly related back to the review sheet that is utilized by staff reviewing a set of Construction Plans that have been submitted for the CSGP.