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Project Planning & Support

There are several important steps in planning a Stream Smart road crossing project.

  1. Inventory and Planning
  2. Technical Assistance
  3. Permitting
  4. Design
  5. Funding
  6. Construction and Monitoring

Inventory and Planning

An inventory of the current road-stream crossing structures that includes information about the condition, type, size, and wildlife barrier status is an important tool for proactive planning. Knowing which structures are priorities for replacement due to infrastructure issues and/or high habitat values allow road managers time to plan, budget, and pursue funding for the most cost-effective outcome.

Inventory and planning resources

The Maine Stream Habitat Viewer is an online map viewer of surveyed road-stream crossings on public roads statewide. As of 2017, nearly 90 percent of Maine’s perennial stream crossings on public roads have been surveyed. Each surveyed crossing includes information about condition, size, and barrier status for fish and wildlife movement, as well as photographs of the site.

The Viewer also offers map layers of high value fish species habitat, including Atlantic salmon and brook trout, as well as data summarizing the habitat values associated with each surveyed road-stream crossing site. The size of the existing structure in relation to the estimated bankfull width of the stream and the number of miles of stream that would be restored if the barrier was replaced with a Stream Smart crossing can be extracted from the attributes at each crossing.

If you have questions about the tool, please contact Sarah Haggerty at Maine Audubon or Alex Abbott at the US Fish and Wildlife Service, Gulf of Maine Coastal Program.

The Maine DOT Work Plan Viewer is an online map of road work planned over the next three years. If a road-stream crossing site has been identified by the road manager as a priority for replacement, planned work by MaineDOT may be an opportunity to collaborate. To be most effective, work with MaineDOT very early in the process.

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Technical Assistance

Building a Stream Smart culvert has many steps and procedures. Technical assistance may be available for project planning, project management, fundraising, on-site assistance, culvert barrier inventories, prioritization, fish and wildlife habitat, structure design, and permitting.

Technical assistance resources

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It is important to find out what permits you may need early in your project planning process. In many instances, you may need both a state of Maine Department of Environmental Protection and a federal Army Corps permit (which have different standards).

Additionally, much of Maine is critical habitat for the federally listed Atlantic Salmon. If you are working in Atlantic Salmon habitat, you will need an Army Corps permit and can receive assistance from the US Fish and Wildlife Service. Contacting agency staff to discuss your project early in the process will help ensure success.

This Flowchart for Stream Crossing Permitting will help you determine what types of permits you may need.

Tips for efficient permitting
  •  Start permitting process as soon as possible
  •  Discuss your project with permitting agencies before submitting application
  •  Provide clear, well-labeled drawings of the crossing design
  •  Meet or exceed design requirements for each reviewing agency
  •  Demonstrate that you pay attention to detail
Elements of a strong permit
  • Speed: the shortest feasible work window will minimize the amount of time the site is opened-up and vulnerable to the elements
  • Erosion control: make sure all exposed soils are protected throughout the process
  • Dewatering and bypass: ensure that you have adequate coffer dams, pumps/hoses and settling basins
  • Stream life is protected: for example, at one crossing, 58,000 fish were moved from the work area to prevent stranding
Resources for state permitting
Resources for federal permitting
Resources for learning about Atlantic Salmon

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A Stream Smart culvert design should follow the 4 S’s:

  • The culvert must SPAN the stream, allowing for passage of aquatic and terrestrial wildlife.
  • The culvert has to be SET at the right elevation.
  • The SLOPE of the culvert must match the stream.
  • There must be SUBSTRATE (natural sediment) in the crossing.

The goal is to let the stream act like a stream and make the road invisible to the stream.

Design resources

Stream Smart Field Assessment Process

All Stream Smart designs start with a field assessment of the construction site. The following measurements should be taken:

  • Longitudinal profile to determine elevation of stream features and slope
  • Cross sections to determine channel width and stream form
  • Substrate assessment, including key pieces and pebble counts

Watch the field assessment video to learn how these field measurements are taken:

Field assessment resources

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Financial assistance may be available for some Stream Smart road crossing projects. Projects with high conservation value for fish passage, such as Atlantic Salmon, alewife, or Eastern Brook Trout, may be eligible for financial assistance through partnership with a conservation program.

NEW in 2022: Maine DEP is administering $3 million dollars from the Maine Jobs and Recovery Act for a single round of grant funding in 2022 to assist municipalities with stream crossing upgrades and replacements and will begin accepting applications in mid-August. These monies fund competitive grants that match local funding for the upgrade of municipal culverts at stream crossings. The projects awarded provide public infrastructure benefits such as by replacing culverts that are currently failing and at risk of complete washouts, opens or improves fish passage, eliminates undersized and other impassable culverts and reduces some of the worst ongoing erosion impacts to streams, brooks, and lakes. DEP expects to open the grant application period on or around August 18, 2022, with application due in November. To help municipalities and others involved with these projects better understand the grant program and requirements, DEP has developed four pre-recorded videos in partnership with Maine Audubon, Maine DOT, and Army Corps of Engineers. Follow this link for details.

Possible funding sources

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Construction and Monitoring

There are many different types of structures that can be used for Stream Smart road crossings. Each stream location is unique and requires its own solution to best meet the 4 S’s.

The following videos demonstrate different construction techniques:

Construction tips
  • Review the plans on-site with principal people and contractors
  • Have materials and equipment on site and ready before breaking ground
  • Stick to the plan, but remain flexible

Visit your site after construction, especially after high flows, to confirm the crossing is working as intended — and to admire your work making real, on-the-ground changes that create longer-lasting roads and support fish and wildlife conservation! In some cases (when funders require it), additional monitoring of stream channel changes provides vital information that demonstrates how successful Stream Smart crossings can be in reconnecting our streams and restoring habitat.

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