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irrigated from the Alamosa River to raise alfalfa, small grains, pastures, and potatoes. <br />Cattle and sheep are also raised in the area. Conejos County is considered the second <br />poorest county in Colorado, with 45.4 percent of the population living below the national <br />poverty level. The town and landownership, within the project area, was established <br />during the mid and late 1800s by Spanish and New Mexican settlers. The population is <br />still predominately Hispanic. <br />The river below Terrace Reservoir is highly unstable and suffers from severe erosion of <br />the stream banks. This condition is the result of a major channel straightening project <br />conducted, in conjunction with the Army Corp of Engineers, in the early 1970s. Many <br />irrigation diversion projects, individual attempts to protect streambanks, and overgrazing <br />of streambank and riparian vegetation also compound the problem. <br />The channel is down cutting in areas. It is over widened and braided in others, causing <br />high bedload deposition which adds to the overall instability. The lack of perennial flow <br />in the stream, during most of the year, inhibits the vegetation growth on the stream banks <br />between the Gunbarrel and County Road 8. All these issues contribute to the high <br />erosion rates and to the bedload entering the river system. The estimated amount of <br />material that was being generated in the 2.5 mile project area prior to construction totaled <br />3212 cu yards per year, or 4,176 tons per year. <br />The goals of this project was to apply Best Management Practices (BMP's) to restore the <br />health of the riparian zone, and to restore the balance of sediment transport continuity <br />through re-establishment of a geomorphically stable stream. <br />This involved physically constructing the correct dimensions or width to depth ratios in <br />the channel, reestablishing the meanders, creating the riffle/ pool sequence that occurs in <br />a natural stable condition, and reconnecting the stream to the old flood plain. Rock vanes <br />were built in the outside bends to direct the stream flows back into the center of the <br />stream, relieving the sheer stress on the riverbanks. Rock cross vanes were placed in the <br />bottom of the stream for grade control. This is to prevent further down cutting of the <br />channel bottom. The USEPA 319 grant program was pursued because of its focus on <br />improving water quality and non-point source pollution. <br />4:' <br />7` <br />2 <br />Rock Vane Structure Rock Cross Vane Structure <br />