New Hampshire is undertaking a variety of efforts to address the impacts of inadequate crossings on river systems and habitat and public safety. In May 2010, DES adopted rules for the permitting of structures for stream crossings. This page will serve as a central location for providing guidance for the design of such crossings, and information about training for those designing, constructing, and maintaining such crossings. The goals of this program are to provide for aquatic life passage during high and low flow conditions and to maximize the passage of high flows, particularly floodwaters, so that losses to infrastructure and adjacent property and public safety are minimized.
New Hampshire Stream Crossing Guidelines 
- Stream Crossing Rules Outreach Presentation - Fall 2010
Determining Watershed Boundaries
Estimation of Flood Flows
Floodplain Maps and Related Information
Fluvial Erosion Hazards
- Fluvial Erosion Hazards and River Geomorphic Assessment Program (Fact Sheet CO-GEO-10)
- Fluvial Erosion Hazards and Geomorphic Assessments in New Hampshire [7.7MB]
- RSA 674:56 Flood Hazards - Authorizing fluvial erosion hazard ordinances
Stream Impairments
Fluvial Geomorphology
- Fluvial Geomorphology Training Module - State University of New York College of Environmental Science and Forestry
- EPA Watershed Academy - Fundamentals of the Rosgen Stream Classification System
- Identification of Bankfull Stage: Videos, CDs, and DVDs
- U.S. Forest Service Stream Systems Technology Center
- Vermont Geomorphic Assessment
- Guidelines for Naturalized River Channel Design and Bank Stabilization (Publication R-WD-06-37)
- Watershed Assessment of River Stability & Sediment Supply (WARSSS)
New Hampshire Studies
- Scientific Basis of Road-Stream Crossing Assessments in the Ashuelot River Watershed
- Stream Crossings in the Ashuelot River Watershed (USEPA)
- River connectivity restoration priorities in High Quality Subwatersheds in Southwest New Hampshire
- Fluvial Geomorphology Assessment of Northern Connecticut River Tributaries - Final Report
- Exeter River Geomorphic Assessment and Watershed-based Plan - Fordway Brook, Upper Exeter River, Dudley-Bloody Brook, and Lower Exeter River
- Exeter River Geomorphic Assessment and Watershed-based Plan - Middle Exeter River
- Oyster River Culvert Analysis Project (2010)
Stream Simulation
- Design and Construction of Aquatic Organism Passage at Road-Stream Crossings: Construction Challenges and Case Studies of Stream Simulation Structures for Aquatic Organism Passage
- Stream Simulation: An Ecological Approach to Providing Passage for Aquatic Organisms at Road-Stream Crossings
- Water-Road Interaction Technology Series Documents
Aquatic Organism Passage
- FHWA- Culvert Design for Aquatic Organism Passage, Hydraulic Engineering Circular Number 26 (October 2010)
- The Vermont Culvert Aquatic Organism Passage Screening Tool
- Maine DOT- Waterway and Wildlife Crossing Policy and Design Guide for Aquatic Organism, Wildlife Habitat, and Hydrologic Connectivity, 3rd edition, 2008
- US Forest Service – Fish Passage Library
- National Inventory and Assessment Procedure – For Identifying Barriers to Aquatic Organism Passage at Road-Stream Crossings
- Design For Fish Passage at Roadway - Stream Crossings: Synthesis Report
Stream Restoration (and Stream Crossings)
- UNH Stream and Wetland Restoration Institute
- Recommended Stream Crossing (Culvert) Assessment Protocol
Resources from Other States
- UMass Amherst: River and Stream Continuity Project
- Massachusetts Stream Crossing Guidelines and Handbook
- Washington State University – Fish Passages for Bridges and Culverts
Other
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