Back - Projects Home PageResults of a Road Crossing Survey

Of The Looking Glass River

During July and August 2001, a team of volunteers conducted visual assessments along the Looking Glass River and on smaller streams that flow into the river. The volunteers were trained to conduct these evaluations by staff from the Michigan Department of Environmental Quality in June 2001. Surveys were completed at 160 locations where roads cross the river and streams, from the beginning of the Looking Glass River in Shiawassee County to its confluence with the Grand River in Portland. Some of the items assessed include the identification of material on the bottom of the river/stream (known as substrate, such as sand, silt, gravel, and cobble), the type of vegetation along the bank (trees, shrubs, grass), surrounding land use (agriculture, residential, wetlands, forest, etc.), potential pollution sources, and the presence of instream cover for fish (vegetation, wood, boulders, pools, undercut banks). Some of the major findings are summarized below.

The bottom substrate at most of the locations consists primarily of sand and/or silt. Gravel and cobble are present at some sites, but generally in small amounts compared to sand and silt. Because aquatic insects (on which many fish feed) prefer hard, stable material such as cobble, the presence of mostly sand and silt will limit the number and types of insects present at many sites. Since the surveys were conducted in July and August, water flow was low and many of the smaller streams were dry. Most of the locations have slow, smooth water flow, with riffles (fast flow, shallow water) and pools (slow flow, deep water) uncommon. The lack of riffles and pools limits habitat diversity in the river and tributary streams. Many of the smaller streams in the watershed have been straightened and dredged, and basically are ditches.

Of the 160 sites that were surveyed, the most frequently observed land use was forest (26%), followed by shrub/old field (21%), residential lawns (19%), row crop/crop residue (14%), and wetlands (13%). It should be pointed out that multiple land uses can be present at one site, for example forest on one side and residential lawns on the other. The fact that much of the surrounding land use is forest, undisturbed old fields, and wetlands is good, since these land uses generally do not harm stream water quality. In addition, the potential for bank erosion appears low, based on volunteer observations. Bank erosion causes sand and dirt to get into the stream, which buries any gravel or cobble substrate on the stream bottom, which insects prefer. Bank erosion potential was rated as none or low at 88% of the sites. Only 11% of the sites had moderate potential for bank erosion, and 1% had a high potential for bank erosion.

The most commonly observed potential pollution source was road/bridge maintenance and runoff (146 observations; note that a source can be identified twice at each site — upstream and downstream). However, the potential impacts of this source was considered small 104 times; potential impacts were considered moderate at 29 sites and high at 13 sites. Other commonly observed potential sources were crop agriculture (87 observations, 24 of which were rated high), removal of riparian vegetation (86 observations, 6 of which were high), bank/shoreline erosion (62 observations, 3 of which were high), residential/urban runoff (55 observations, 4 of which were rated high), dredging (50 observations, 4 of which were rated as high), and road/bridge construction (32 observations, 8 of which were rated as high).

Because no actual water quality monitoring took place during the road crossing surveys, the characteristics described above can only suggest potential problems, not actual problems. Therefore, the results of the road crossing survey were used to identify 21 sites that seem most likely to have problems. These 21 sites will be assessed in more detail in 2002. Specifically, volunteers will be trained by DEQ staff on Saturday, April 13, 2002, to collect and identify aquatic insects and other invertebrates in the river or stream. The types and numbers of aquatic invertebrates found in a stream are used to indicate whether water quality is good or bad. The instream monitoring will be conducted at the 21 priority sites in both the spring and fall 2002. Other sites can be added depending on volunteer interest (the more volunteers we have, the more sites we can assess) and new information. Some of these locations likely will be monitored in future years as well, whereas others may be in good condition and will not require future sampling. New sites will be monitored in future years based on available information and potential for problems.

Once degraded sites are found, the final step of the process is to identify the cause of the problem and to correct it. Depending on the problem, cooperation from many groups may be required, including nearby landowners, businesses, city/county/township governments, drain commissioners (primarily from 3 counties), and road commissions. The goal of the Friends of the Looking Glass River is to correct identified problems primarily through cooperation, partnership, and education. A clean, healthy Looking Glass River, including its smaller tributary streams and ditches, will benefit everyone.