In 2003 CRWD assumed an advisory role to its cities on development and redevelopment proposals: District staff would review development proposals and make recommendations consistent with the guidelines for water quality, volume control, flooding, rate control, wetland protection, and erosion control in CRWD’s Development Review Criteria. In two years, the District reviewed 71 developments, tracked criteria implementation, and found marginal compliance.
With water quality goals not being advanced, in 2005 CRWD completed a study to assess the pollution impacts of non-compliance with the Development Review Criteria and then set a goal to develop and adopt science-based watershed rules to improve water quality.
Water quality and stormwater management rules (Rules) were adopted by CRWD Board of Managers in September 2006, and subsequently a Permitting Program was created as a vehicle for the Rules’ implementation. The Rules require stormwater management permits for construction projects disturbing more than one acre of land. Most of CRWD is fully developed, making it necessary to utilize stormwater improvement technologies as part of redevelopment projects to reduce stormwater pollution to CRWD’s lakes and wetlands and the Mississippi River. In order to achieve CRWD’s goal of cleaner water resources, the Rules require volume reduction practices that capture one inch of rainfall over all newly constructed impervious surfaces. This is most often achieved by infiltration of runoff into the soil.
Permits are required for projects under the following rules and have the following requirements:
Rule C. Stormwater Management:
Permit required for projects disturbing greater than one acre of land, or 10,000 square feet of land adjacent to a waterbody and repairs, replaces, or creates impervious surface.
Applicants are required to meet three stormwater management standards:
- Rate control – Runoff rates shall not exceed existing runoff rates for the 2-year, 10-year, and 100-year critical storm events.
- Volume reduction – Stormwater runoff volume reduction shall be achieved onsite in the amount of one inch of runoff from impervious surfaces.
- Water quality – Stormwater BMPs shall remove 90% of total suspended solids from the runoff generated by a 2.5-inch rainfall event (NURP water quality storm).
Rule D. Flood Control:
Permit required if within the 100-year floodplain of a waterbody. A floodplain is the area adjoining a watercourse or natural or man-made waterbody, including the area around lakes, marshes and lowlands that is inundated during a 100-year flood.
No placement of fill within the 100-year floodplain is allowed unless compensatory storage is provided. Compensatory storage must be provided on the development or immediately adjacent to the development within the affected floodplain.
Rule E. Wetland Management:
Permit required for any work that may fill, drain, excavate, or otherwise alter the character of a wetland. The District wetland rule adopts by reference the MN Wetland Conservation Act (WCA) with the following exceptions..
(1) The de minimis size will be zero.
(2) Flexibility Sequencing will not be allowed.
(3) Public Value Credits can not be used for replacement.
(4) All other WCA non-temporary impact exemptions to wetlands will not be allowed.
(5) All wetland replacements shall be within the Districts boundaries.
The following steps are required for projects that will drain, fill or excavate wetlands:
- Attempt to avoid direct and indirect impacts to wetlands;
- Minimize impacts to wetlands by limiting the degree or magnitude of wetland activity;
- Rectifying temporary impacts by repairing, rehabilitating, or restoring the affected wetland;
- Reducing or eliminating impacts to wetlands over time by preserving the wetlands through proper maintenance, management, and operation of the project to avoid further draining or filling of wetlands, and
- Replace unavoidable wetland impacts by replacing with wetland areas of equal or greater public value.
Rule F. Erosion and Sediment Control:
Permit required for any land disturbing activity over one acre, or greater than 1,000 square feet and adjacent to a waterbody or within the 100-year floodplain.
Applicants are required to prepare an erosion and sediment control (ESC) plan that meets the following requirements:
- ESC plans shall comply with the standards of the MN Pollution Control Agency’s NPDES General Construction Permit except where more specific standards are required.
- Natural site topography and soil conditions shall be used to control runoff and reduce erosion and sedimentation.
- Construction activity shall be phased when possible.
- All construction waste shall be properly managed and disposed.
- All erosion and sedimentation controls shall be installed before commencing the land disturbing activity.
- The permittee shall be responsible for proper operation and maintenance of all controls.
Rule G. Illicit Discharge and Connection:
Permit required for new direct connections orreplacement of existing connections to the Trout Brook Storm Sewer Interceptor or other components of CRWD’s municipal storm sewer system. CRWD must approve the methods for making a new direct connection or replacing an existing connection.
Peak flow rate and the total volume of flow must not cause new water conveyance problems or exacerbate existing water conveyance problems. Enlargement of existing connections is considered a new connection.
CRWD strongly recommends that any developer review a full copy of CRWD’s Complete Rules Document to learn about all criteria and requirements for a permit.
Also see the Volume Reduction for Stormwater Management FAQ Sheet or Permit Guidance and Information Handbook.
Statement of Need and Reasonableness (SONAR)
As part of promulgating the Rules pursuant to State statutes, a statement of need and reasonableness for CRWD Rules was prepared to justify the need for the Rules. The SONAR contained two sections: 1) description of the need for CRWD Rules; and 2) description of why CRWD believes that the Rules are reasonable.
CRWD, partnering with Ramsey-Washington Metro Watershed District, completed the Rulemaking Study to evaluate how stormwater BMPs should be incorporated into densely developed sites, develop the technical standards/criteria for the Rules, and evaluate how the technical standards apply to the same sites evaluated previously. This study illustrated that the technical criteria for the Rules were practical and feasible from an engineering perspective and the costs were reasonable in consideration of the total project cost. Read the full document.
Appendix A, Establishment Order
Appendix B, Section IV-7 of Watershed Management Plan
Appendix C, MOUs
Appendix D, Development Review Criteria
Appendix E, Development Review Compliance Tables
Appendix F, Development Impact Analysis
Appendix G, Rulemaking Workplan and Timeline
Appendix H, Rulemaking Study, Phase I
Appendix I, Technical Standards for Rules
Appendix J, Rulemaking Study, Phase II
Appendix K, Draft Rules 10_05_05
Appendix L, Oct-Dec 2005 Comments
Appendix M, TAC Workplan Schedule
Appendix N, TAC Recommendations and Documents
Appendix O, District Response to TAC Recommendations
The Board of Managers has adopted resolutions to establish the rules and the associated fees. Click here to view the 2008 resolutions.