Restoring fish, flow in the St. Joseph River watershed
April 11, 2013
Since the beginning of time - or at least since before 1863 - the St. Joseph River has meandered unfettered for 210 miles from its origins at Baw Beese Lake in Hillsdale County to Lake Michigan at the cities of St. Joseph and Benton Harbor. Considering the numerous tributaries flowing into the St. Joseph River, the watershed encompasses more than 1,800 stream miles.
Before 1863, when the city of Niles constructed the first dam on the river, fish moved freely throughout the river system. Since that time, numerous man-made impediments to fish passage have been constructed on the river and streams in the watershed. By the late 1990s, there were 190 registered dams on the St. Joe and its tributaries as well as uncounted unregistered barriers.
Although these dams have provided some economic and recreational benefits, they have adversely affected fish communities by blocking spawning migrations, interfering with seasonal movements, and fragmenting populations. Dams also influence fish habitat by blocking downstream movement of large woody structure and detritus (e.g., small pieces of wood and leaves), disrupting the sediment balance above and below impoundments, altering flow regimes and channel dimensions, and elevating stream water temperatures.
Many of the dams across Michigan are near the end of their life expectancy and no longer fulfill their original purposes. These dams are excellent candidates for removal.
In 2010, the Potawatomi Resource Conservation and Development Council received a grant through the United States Fish and Wildlife Service's (USFWS) Fish Passage Program to identify such dams within the St. Joseph River watershed. The Michigan Department of Natural Resources (DNR) assisted with this effort, along with personnel from the Indiana Department of Natural Resources, Southwest Michigan Planning Commission (SWMPC), Friends of the St. Joseph River Association, United States Army Corps of Engineers, various conservation districts and two private consulting firms (Fishbeck, Thompson, Carr, and Huber, Inc. and Streamside Ecological Services, Inc.).
This conglomeration of governmental agencies and other organizations has come to be called the Fish Passage Group.
The Fish Passage Group compiled information from existing sources into a centralized database. It was not feasible to conduct field reviews for all of the dams, so a ranking system was used to identify which of those dams merited site inspections. During 2011, inspections were completed at 43 dam sites. Out of this sample, the Fish Passage Group determined that 22 dams no longer exist or have been bypassed and do not function as migration barriers for fish. Fourteen of the remaining dams were identified as high-priority candidates for removal. During the next phase of the process, the DNR or partner organizations will contact the owners of these dams to determine if they are interested in removal.
The DNR has already assisted with several dam removal projects in the St. Joseph River watershed. For example, DNR Fisheries Division staff partnered with the DNR Parks and Recreation Division's heavy equipment crew to remove the Jonesville Dam on the upper St. Joseph River in January 2011.
The DNR also provided funding and technical assistance for the removal of the Watervliet spillway and diversion dams on the Paw Paw River during fall 2011. This large-scale project involved the collaboration of multiple organizations (including Environmental Consulting & Technology, Inc., SWMPC, the Nature Conservancy, Two Rivers Coalition and the City of Watervliet) and funding from the National Oceanic and Atmospheric Administration, USFWS, and Berrien County.
"Dams are not the only barriers restricting movement of fish within the river system," explained DNR fisheries biologist Brian Gunderman. "Undersized or misaligned stream crossings - such as perched culverts - also can prevent upstream passage of fish.
"During 2010 and 2011, the Fish Passage Group conducted inspections at 101 crossings on seven different streams and approximately one-third of these crossings were determined to be barriers to some or all fish species or life stages under most flows."
The DNR and partner organizations are working to eliminate these barriers to fish passage.
The Michigan Department of Environmental Quality, the DNR and SWMPC helped the Berrien County Road Commission obtain a USFWS Fish Passage Grant to replace one particularly bad crossing on a small tributary to the St. Joseph River near the town of Buchanan.
A perched culvert has hindered movement of fish into this cold-water stream. The culvert was also undersized, and water overtopped the road after major storm events. During fall 2012, this crossing was replaced and grade-control structures were installed downstream. These improvements have reduced the risk to public safety and will allow salmon, steelhead and brown trout to access valuable spawning and nursery habitat.
The Michigan Department of Transportation also has made modifications to the M-139 crossing of Big Meadow Creek in Berrien County to improve upstream fish passage.
It took more than a century for humans to construct all the barriers in the St. Joseph River watershed. Removal of those barriers will not occur overnight. With help from a wide range of partners, the DNR has begun the process of reconnecting stream reaches and restoring fish populations in this major river system. Over time, fish movement in the St. Joseph River system will return to a more natural state of affairs.
To find out more about how the DNR manages dams, visit www.michigan.gov/dnrdams.