Massachusetts Crossing Standards
The Massachusetts River and Stream Crossing Standards were developed by the River and Stream Continuity Partnership with input from an Advisory Committee that includes representatives from UMass-Amherst, MA Riverways Program, Massachusetts Watershed Initiative, Trout Unlimited, The Nature Conservancy, the Westfield River Watershed Association, ENSR International, the Massachusetts Highway Department, and the Massachusetts Departments of Environmental Protection and Conservation and Recreation.
In developing the standards, the Partnership received advice from a Technical Advisory Committee that included representatives of the US Fish and Wildlife Service, USGS BRD, US EPA, US Army Corps of Engineers, MA Division of Fisheries and Wildlife, American Rivers, Connecticut River Watershed Council, Connecticut DEP, a hydraulic engineering consultant, as well as input from people with expertise in Stream Simulation approaches to crossing design. The standards are intended to serve as recommended standards for permanent crossings (highways, railways, roads, driveways, bike paths, etc) on fish-bearing streams and rivers, and as guidelines for upgrading existing crossings when possible. These standards seek to achieve, to varying degrees, three goals:
Fish and other Aquatic Organism Passage : Facilitate movement for fish and other aquatic organisms, including relatively small, resident fish, aquatic amphibians & reptiles, and large invertebrates (e.g. crayfish, mussels).
River/stream continuity : Maintain continuity of the aquatic and benthic elements of river and stream ecosystems, generally through maintenance of appropriate substrates and hydraulic characteristics (water depths, turbulence, velocities, and flow patterns). Maintenance of river and stream continuity is the most practical strategy for facilitating movement of small, benthic organisms as well as larger, but weak-swimming species such as salamanders and crayfish.
Wildlife Passage : Facilitate movement of wildlife species including those primarily associated with river and stream ecosystems and others that may utilize riparian areas as movement corridors. Some species of wildlife such as muskrats and stream salamanders may benefit from river and stream continuity. Other species may require more open structures as well as dry passage along the banks or within the streambed at low flow.
These Crossing Standards adopt a “Stream Simulation” approach for crossing design in order to better protect river and stream ecosystems. Stream Simulation is a design approach that avoids flow constriction during normal conditions and creates a stream channel that maintains the diversity and complexity of the streambed through the crossing. Crossing structures that avoid channel constriction and maintain appropriate channel conditions (channel dimensions, banks, bed, and bed forms) within the structure should be able to accommodate most of the normal movements of aquatic organisms, and preserve (or restore) many ecosystem processes that maintain habitats and aquatic animal populations. The goal is to create crossings that present no more of an obstacle to movement than the natural channel and that are essentially “invisible” to aquatic organisms.
These guidelines are for general use to address issues of river and stream continuity, fish passage and wildlife movement. In some cases, site constraints may make strict adherence to the standards impractical or undesirable. For example, in some situations the road layout and surrounding landscape may make it impossible or impractical to achieve the recommended standards for height and openness. These standards may not be appropriate for highly degraded streams where stream instability may be a serious concern. Site-specific information and good professional judgment should always be used to develop crossing designs that are both practical and effective.
Here are some important considerations to keep in mind when using these standards.
They are intended for permanent river and stream crossings. They are not intended for temporary crossings such as skid roads and temporary logging roads.
They are generally intended for fish-bearing streams. However, these standards may be useful in areas where fish are not present but where protection of salamanders or other local wildlife species is desired. Further, the standards are not intended for drainage systems designed primarily for the conveyance of storm water.
These standards were developed with the objective of facilitating fish and wildlife movement and the preservation or restoration of river/stream continuity. They may not be sufficient to address drainage or flood control issues that must also be considered during design and permitting of permanent stream crossings.
These standards are not prescriptive. They are intended as conceptual performance standards for river and stream crossings. They establish minimum criteria that are generally necessary to facilitate fish and wildlife movement and maintain river/stream continuity. Use of these standards alone will not satisfy the need for proper engineering and design. In particular, appropriate engineering is required to ensure that structures are sized and designed to provide adequate capacity (to pass various flood flows) and stability (bed, bed forms, footings and abutments).
The design of any structure must consider the channel type and long profile and must account for likely variability of the stream or river for the life of the structure.
In urbanizing environments there is greater potential for land use changes to result in stream instability. Wherever there is potential for stream instability it is important to evaluate stream adjustment potential at the crossing location and to factor this into the design of the structure.
Click on the following link to download a copy of the Massachusetts River and Stream Crossing Standards.