B. Considerations Before Drainage Work is Done Revision as of 19:28, 12 April 2017 by Tgillette (talk | contribs)(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff) B. Considerations Before Drainage Work is Done

1. Environmental, Land Use, and Multipurpose Water Management Criteria

Minn. Stat. § 103E.015, subd. 1 requires that the drainage authority “must consider” nine criteria relating to land use and the environment for a 103E drainage project. How these criteria are to be considered is not prescribed in law. However, individuals, organizations or agencies may be able to provide input on a site by site basis to support the drainage authority’s decisions. Permits may be required for portions or all of a drainage project. However, the environmental considerations in 103E.015 must be addressed regardless of whether a drainage project requires a permit or not. The engineer should be requested by the drainage authority to summarize these considerations within the engineer’s reports. The drainage authority may provide the engineer specific expectations as to the content and level of detail to be provided in the engineer's report beyond the minimum statutory requirements.

Some general guidelines for the scope and application of these considerations are described as follows, as described in Minn. Stat. § 103E.015, Subd. 1:

1. Private and public benefits and costs of the proposed drainage project; This discussion should be more global in nature, addressing such non-quantifiable factors as environmental costs, public costs, cultural costs, etc. where applicable. Discussion of benefits and costs should not be limited to financial considerations alone.

2. Alternative measures, including measures identified in applicable state-approved and locally adopted water management plans, to:

(i) Conserve, allocate, and use drainage waters for agriculture, stream flow augmentation, or other beneficial uses;

(ii) Reduce downstream peak flows and flooding;

(iii) Provide adequate drainage system capacity;

(iv) Reduce erosion and sedimentation; and

(v) Protect or improve water quality.

The engineer should be aware of (and, where applicable, specify within the preliminary engineer’s report) local water management plans such as WRAPS, TMDLs, watershed plans, and county water plans (See Appendix 13) and their applicability for the drainage project. Chapter 5 of this manual provides a matrix for Best Management Practice selection to assist in BMP implementation within the context of a public drainage system and/or its watershed.

3. The present and anticipated land use within the drainage project or system, including compatibility of the project with local land use plans;

Change in land use can have substantial effects on the performance of a public drainage system. Local land use plans should be considered prior to the start of project design.

4. Current and potential flooding characteristics of property in the drainage project or system and downstream for 5-, 10-, 25-, and 50-year flood events, including adequacy of the outlet for the drainage project;

The preliminary engineering report should identify particular flooding issues (e.g., high ground water, spring flooding, crop damage from summer storms, inadequate outlet, etc.). The engineer should consider estimating the number of acres directly affected by the identified flooding problems. Section 5 of this chapter provides additional detail for considerations of the adequacy of the outlet.

5. The effects of the proposed drainage project on wetlands;

Drainage projects must comply with a variety of state and federal wetland regulations (see Chapter 3, Section 2.B Wetland Regulation). The engineer should consider avoidance of impacts to wetlands (including those considered “exempt”) and/or wetland enhancements in development of project alternatives. Avoidance measures might include utilizing non-perforated tile under wetlands, realignment of the public drainage system around a wetland, or utilizing risers to maintain or increase wetland hydrology.

6. The effects of the proposed drainage project on water quality;

Water quality issues pertinent to drainage projects include erosion potential (before and after), sediment transport, and non-point pollution (e.g. nutrients, pesticides, and bacteria), etc. Chapter 5 of this manual can help the engineer select BMPs (including wetland restoration and creation) that can address these issues based on the source/ symptom/ causes encountered during the engineering survey. See Chapter 3, Section 2.F. Water Quality for more detail.

7. The effects of the proposed drainage project on fish and wildlife resources;

Fishery impacts include sedimentation along downstream areas after construction, blockage of fish movement due to grade control structures, and excessive water velocities created by hydraulic structures. Wildlife may be impacted by potential land use changes, including the destruction of prairie and wooded habitat. The grass buffer strip requirement for drainage systems should not be suggested as providing adequate mitigation for the destruction of other wildlife habitat. The DNR fisheries and wildlife managers and other natural resource professionals are a source to consult for assistance in identifying potential project impacts and mitigation measures.

8. The effects of the proposed drainage project on shallow groundwater availability, distribution, and use; and

Where shallow ground water conditions exist, either on a sustained or a seasonal basis, it is possible for a drainage project to have significant impact on normally experienced water levels. As with any other affected resource, impacts should be discussed and possible alternatives evaluated.

9. The overall environmental impact of all the above criteria.

Potential negative impacts of the proposed drainage project should be clearly identified and discussed for the benefit of the drainage authority.

These criteria will be referred to frequently in the remaining sections of this chapter. It should be noted that these criteria encompass much more than engineering related concerns. They provide a framework for evaluating project impacts, including engineering, social, economic and environmental issues. The engineer should review these criteria and assess their impact on a proposed drainage project as soon as possible after the project is initiated (see Appendix 1 for a checklist of Minn. Stat. 103E.015 criteria).

2. Investigating External Sources of Funding and Technical Assistance

There are many external funding sources to complete projects, including the Clean Water Fund, administered through BWSR, DNR, MDA, and MPCA.

Minn. Stat. § 103E.015, Subd. 1a requires the drainage authority and, therefore, the Engineer, to investigate the potential use of external sources of funding to facilitate the purposes of wetland preservation or restoration, creation of water quality improvements, or flood control, as authorized in Minn. Stat. § 103E.011, Subd. 5 (see Appendix 2 for an external funding sources checklist).

Note that Minn. Stat. § 103E.011, subd 5 also authorizes the use of external funding and drainage system assessed funds within the watershed of the drainage system (not just the benefited area) for the purposes specified.

The sources of external funding may include local, state, federal, or private funding. Potential sources of state funding may include the Clean Water Fund (administered through the Board of Soil and Water Resources, Department of Natural Resources, Department of Agriculture, and Minnesota Pollution Control Agency), Outdoor Heritage Fund (administered by the Lessard-Sams Outdoor Heritage Council), and Flood Hazard Mitigation Grants (administered by the Department of Natural Resources). Potential federal funding sources may include the Environmental Quality Incentives Program (EQIP) and Wetland Reserve Easements Program (WREP), both administered by the Natural Resources Conservation Service. Early coordination with the local soil and water conservation district is recommended to help identify potential and likely funding sources.