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Watershed and DNR Dispute Resolution
Projects that require permits from both the Minnesota Department of Natural Resources (DNR) and local watershed districts are problematic when the two agencies do not agree. The Minnesota DNR has specific rules that must be followed. For new stream crossings (no existing structure) the stage increase for the 100-year flood typically must be limited to 0.5 feet. For the replacement of an existing structure, the stage increase is, in general, limited to that of the inplace condition (if greater than 0.5 feet). Watershed district requirements are usually spelled out in the rules developed by each specific watershed district. Problems occur when the goal of the watershed district is to reduce downstream flooding by restricting the flow of water through roadway structures.
On occasion, the rules of the Minnesota DNR and a watershed district may disagree. This disagreement should be addressed early in the project development process to minimize potential delays. The hydraulic analysis for stream crossings should be done as early as possible and submitted to both agencies to see if any conflicts exist between the rules of the watershed district and the DNR. If the proposed structure does not meet the requirements of both entities, it is recommended that the Engineer meet with the two agencies to resolve the differences and determine the structure each agency can endorse.
If a decision cannot be reached regarding the size of a stream crossing, the Engineer may take the next step and request the assistance of the Board of Water and Soil Resources (BWSR). The Engineer may request BWSR to assist in resolving the question through an informal resolution process, but if the question of structure size cannot be resolved informally, the next step is to request a petition for intervention by BWSR. This procedure is outlined in Minnesota Statutes 103A (see sections .301 to .341). In summary, early coordination with the local watershed district and the DNR is the best action. If the determination of structure size cannot be made in conjunction with the two agencies, then the resolution process with BWSR should be used.
Another problem issue is the hydraulic sizing of structures on county ditches. The regulations regarding county ditches are found in Minnesota Statutes 103E. Hydraulic capacity is discussed in 103E.525, and construction of bridges and culverts of insufficient capacity is addressed in 103E.075. It appears that if a transportation agency should decide to construct a hydraulically smaller drainage structure, it could be in violation of Minnesota Statute 103E.075.
The Office of State Aid for Local Transportation (SALT) has reviewed the issue of funding for these stream crossings. Where State Bridge Funds (Bond Funds) or Town Bridge Funds are used, the culvert or bridge must be sized in accordance with requirements in the State Aid Manual, Section 5-892.225, summarized below:
- The waterway opening required for the structure must be determined by a registered engineer and supported with a written and signed hydraulics letter or report containing the required information in State Aid Manual, Figure B 5-892.225.
- A Risk Assessment (State Aid Manual, Figures C 5-892.225) must be completed for the recommended waterway opening or additional risk analysis provided.
- The waterway opening selected must be the one with "the lowest acceptable grade line and the smallest waterway opening consistent with the constraints imposed on the projects." The design engineer makes this judgment and documents it by signing the Risk Assessment.
- Where a regulatory agency, as a condition to receive a permit to construct the bridge, demands a design which may be inconsistent with the items above, bridge funds may still participate in the full cost of the bridge, provided the design engineer (or other engineer) supplies the required hydraulic data and a completed Risk Assessment for the required size. The State Aid Manual states, "the stage increase generated by the proposed bridge should comply with the requirements set forth by the affected agencies."
- Bridge Funds will not participate in the additional size of structures where the increased opening is not required for hydraulic considerations or a condition of regulatory approval.
Mr. James Haertel, BWSR Water Management Specialist, provided input regarding the problem resolution process with BWSR. Mr. David Phillips, Assistant Attorney General, provided input regarding hydraulic sizing of structures on county ditches.