Designated Beneficial Uses
At the recommendation of the Department of Natural Resouces, the Missouri Clean Water Commission determines the quality of water necessary to attain designated "beneficial uses" on Missouri streams. Eighty-three miles of the North Fabius, 64 miles of the Middle Fabius, and 67 miles of the South Fabius rivers and the lower 3.5 miles of Troublesome Creek are designated for public drinking water supply (MDNR 1986a). All basin streams are designated for livestock and wildlife watering and protection of aquatic life. No streams in the basin are classified for whole-body contact recreation.
The primary deterrents to recreational use in the basin are high turbidity and siltation, which are direct results of poor soil management (MDNR 1986b). Excessive turbidity and siltation have not only decreased the abundance and diversity of aquatic life and habitat (Missouri Department of Conservation 1978), but have also made boating and canoeing more difficult due to locally heavy sedimentation. Stream channelization, which has also drastically reduced the amount and quality of aquatic habitat in parts of the basin, especially in the North Fabius River (Turner 1978), has affected recreational use by creating high banks and steep-sided channels where access is difficult. The lack of public access in parts of the basin also limits recreational use.
Chemical Quality of Stream Flow
Water quality data have been collected intermittently since 1972 at the South Fabius River gage station (USGS 1986, 1993; Table Wq01). A typical water year (1986) and a flood year (1993) were chosen for comparison. Both iron and manganese sometimes exceed secondary drinking water standards in the South Fabius River. Groundwater quality is considered poor throughout the basin due to high concentrations of dissolved solids and iron (MDNR 1986a, 1986b).
Water quality surveys were conducted in the Middle Fabius River, Troublesome Creek, and Grassy Creek by the Soil Conservation Service during 1975-1976 (Table Wq02 and Wq03). Elevated levels of dissolved solids, ammonia, coliform, nutrients, and pesticides were recorded in these streams during 1975-1976. Total iron concentrations sometimes exceeded maximum drinking water quality standards for dissolved iron by a factor of ten or more. Presumably, much of the iron measured during these periods was attached to soil particles as insoluble ferric (Fe+3 ) ions (Soil Conservation Service 1977). High levels of bacteria, suspended solids, and nutrients were usually associated with periods of high flow. Department of Conservation personnel collected water quality information from three sites in Troublesome Creek during 1988-1992 (Table Wq03).
Non-Point Source Pollution
Sedimentation and turbidity are the basin's most severe water quality problems. Intensive crop farming and livestock grazing have caused severe soil erosion throughout the watershed. Anderson (1980) reported 18-24 tons/acre/year of sheet and rill erosion from tilled land in the basin. Erosion from permanent pasture land averaged 5-9 tons/acre/year. Gully erosion in the drainage was among the most severe in the state, averaging 500-750 tons/square mile annually. As a consequence, the watershed delivered about 3.7 tons/acre of sediment to streams annually and was ranked the fifth worst of 45 basins in the state. Streambank erosion is also a problem in the basin. In the upper and lower Middle Fabius sub-basins, streambank erosion was estimated at 380 tons/square mile/year and 160 tons/square mile/year, respectively (SCS 1978).
Agricultural run-off, which includes fertilizer, pesticides, herbicides, and animal waste, also poses a significant threat to water quality in the basin. Excessive aquatic plant growth (mostly algae) has been observed periodically in several basin streams (MDC 1978). Although fish kills in the basin are uncommon, they usually can be attributed to low dissolved oxygen concentrations or high levels of ammonia entering the stream from animal feedlots or sewage lagoons.
Point-source pollution is low in the basin (Table Wq04). There are nine small communities that operate wastewater treatment facilities. Only three (Edina, Lancaster, and Memphis) discharge more than 0.06 MGD (million gallons daily) of sewage into receiving streams. Numerous small privately owned point-source discharges (mobile home parks, schools etc.) occur in the basin. Stormwater run-off from eight mining quarries and one petroleum storage facility are also potential point sources of pollution, but none have been linked to pollution events significant enough to cause a fish kill.
Concentrated Animal Feeding Operations
CAFOs are expanding in the basin, especially in the Troublesome Creek watershed, where they may have significant negative impacts on water quality. Currently, the only significant CAFO in the basin is a large dairy operation located in the Troublesome Creek watershed, Lewis County (s4 T60n R9w). Chronic releases of lagoon effluent from this facility directly into Troublesome Creek during the late 1990s may have caused significant damage to aquatic life.