Officials from the Colorado State Office of the U.S.D.A.’s Natural Resources Conservation District have detailed their engineering design plans to repair a floodwater control dam south of Canon City. The N.R.C.S. staff members reported to the Fremont County Commissioners and citizens at a July 7th meeting that plans are to complete the design work and bidding process so that reconstruction of the C-4 Dam can get underway this fall. The C-4 Dam was built in 1971 and is designed to hold 213 acre feet of stormwater which would be released at a slower rate to protect some 500 residences in the Lincoln Park neighborhood. The dam is located on the north side of the Shadow Hills Golf Course.
N.R.C.S. State Conservation Engineer John Andrews reported that half-inch to three inch holes that were found in the 1980’s developed into larger sink holes over the years. He explained that such subsidence has been found to be a problem with soils in dams built in desert areas of the southwest. Andrews said the engineers’ investigation revealed cracks at least 25 feet deep and were as wide on the bottom as they were on the top.
Andrews said the N.R.C.S. repair plan calls for excavating the face of the dam where cracking has occurred and then replacing it with compacted soil down to bedrock. He said that will prevent water from destabilizing the base of the dam above bedrock. He said the height of the dam would be raised about 1 ½ feet.
After engineering design is completed this summer Andrews said the N.R.C.S. will turn over design specifications to the Fremont County Commissioners so a construction contract can be bid and awarded. The construction would take about four months to complete next winter or early spring. Andrews said normally it takes about two years of review but because of concerns to the Lincoln Park community they’ve made it a priority to get it all done in about nine months.
Federal funding will finance 90 percent of the project while Fremont County will contribute the other ten percent in matching funds.
The State Engineer issued an order last year for the County to either repair the dam or breach it. Fremont County Emergency Management Director Ray Southard is again keeping a close eye on developing thunderstorms as the summer monsoon season approaches. He says the County wants to make sure citizens have ample warning should heavy rain raise any safety concerns about the stability of the dam.
N.R.C.S. State Conservation Engineer John Andrews reported that half-inch to three inch holes that were found in the 1980’s developed into larger sink holes over the years. He explained that such subsidence has been found to be a problem with soils in dams built in desert areas of the southwest. Andrews said the engineers’ investigation revealed cracks at least 25 feet deep and were as wide on the bottom as they were on the top.
Andrews said the N.R.C.S. repair plan calls for excavating the face of the dam where cracking has occurred and then replacing it with compacted soil down to bedrock. He said that will prevent water from destabilizing the base of the dam above bedrock. He said the height of the dam would be raised about 1 ½ feet.
After engineering design is completed this summer Andrews said the N.R.C.S. will turn over design specifications to the Fremont County Commissioners so a construction contract can be bid and awarded. The construction would take about four months to complete next winter or early spring. Andrews said normally it takes about two years of review but because of concerns to the Lincoln Park community they’ve made it a priority to get it all done in about nine months.
Federal funding will finance 90 percent of the project while Fremont County will contribute the other ten percent in matching funds.
The State Engineer issued an order last year for the County to either repair the dam or breach it. Fremont County Emergency Management Director Ray Southard is again keeping a close eye on developing thunderstorms as the summer monsoon season approaches. He says the County wants to make sure citizens have ample warning should heavy rain raise any safety concerns about the stability of the dam.