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DAM SAFETY Recreationists return to Horsetooth After nearly 4 years, $77 million and almost 26,000 truckloads of sand and gravel, the U.S. Bureau of Reclamation project to renovate Horse- tooth Reservoir's four earthen dams is basically complete. That means the water level will be allowed to return to its capacity for the first time since 1999. To reduce seepage from the dam, USGR originally intended to install a concrete cutoff wall through Horsetooth Dam's middle but later scrapped that plan in favor of a 2- to 3 -foot clay and synthetic "blanket" covering the base of the dam. It's designed to prevent seepage through the foundation of the dam and also comes at a savings of $19 million. The entire project comes in $28 million under its $105 million budget. Monitoring and surveillance of the dams will continue. Gauges known as piezometers have been installed in each of the dams – in- cluding more than 20 in Horsetooth Dam along – to track water pressure. Fort Collins Coloradoan, October 22, 2003 Senator seeks dam safety funds A measure has been introduced in the U.S. Senate that would authorize nearly a five -fold funding increase – exceeding $500 million a year – to improve the safety of aging dams in Colorado and across the West. The measure by Sen. Pete Domenici, R -N.M., would amend the 1978 Safety -of -Dams Act by increasing authorized appropriation levels to $540 million annually for USBR dam safety projects. The Act funded the nearly complete $77 million renovation of four dams at Horsetooth Reservoir west of Fort Collins. Fort Collins Coloradoan, October 22, 2003 DROUGHT Three - quarters of American West still considered in drought Water experts attending a national conference in Denver say more than 75 percent of the American West still is deep in a drought, and no one knows how long it will last. The conference, Water 2025, was part of a federal initiative launched by Interior Secretary Gale Norton in June. So far, more than 3,000 people have gathered at nine conferences to identify ways to better manage and share the West's water supplies. One of the concerns discussed was a forecast from the U.S. Geological Survey that temperatures could rise an average of 5.4 degrees by as early as 2025. That would change the spring runoff from the mountains, affecting supplies, evaporation, stream flow and temperatures and fish health. Associated Press / Durango Herald / November 5, 2003 Global warming could overburden city system A recent city- sponsored study by Hydrosphere Resource Consultants concluded that a little conservation would give Boulder enough water to meet the demand of future growth in non - drought years. But if global warming dries the area, the city's current system won't be able to quench the population's thirst. The study completed for the city's water utility and Planning Department in September looked at Boulder's water rights, typical stream flows, 300 years of tree ring data and various levels of future population and job growth in the city. It calculated whether Boulder would have enough water to meet city service standards under historic weather averages and if global warming cut stream flows by at least 15 percent. If Boulder grew to a population of 126,300 residents and was home to 216,700 jobs — the "build out" levels un- der current zoning — some conservation measures would give the city a reliable enough water supply to meet its minimum service standards. In a climate made hotter, drier and with more dramatic weather swings due to global warming, the city would need to increase its reservoir storage space or cut the typical household's use, the study found. "The chance that climate change could overburden Boulder's current water supply is enough to warrant beginning to plan for it," said Steve Pomerance, a former City Council member long concerned about water re- sources and future growth in the city. Boulder Daily Camera / November 3, 2003 SALINITY River salinity study / Too much salt for maximum yields Tim Gates of Colorado State University has been studying salinity in the soil and water of the Arkansas Valley for five years, with sometimes surprising results. Gates began his study in the area between Manzanola and John Martin Reservoir for the first three years, and last year expanded it to include the area downstream from John Martin to the Kansas border. The problems being studied are high water tables which create waterlogged and saline soils and reduce the yield of farm crops; and dissolution of salts within the aquifer, which carries salts and other pollutants back into the river. Salinity increases from west to east along the Arkansas Valley, but the bulk of the salts are inherent in the soil rather than being transported from upstream reaches of the valley, Gates told the Southeastern Colorado Water Conservancy District board. In the blistering drought of 2002, both the depth of the water table and the salinity level in ground water diminished. "It's interesting that as the water table falls the salinity also falls," Gates said. "The (geologic) formations where the salts are being dissolved are in the upper levels of the water table." But even the drought- reduced levels of salinity, and even in the least saline areas, the soil salts are too high for maximum crop yields, he said. He estimates crop yield reduction at 13 percent, or $68 lost per acre, between 1999 and 2001 in the upstream study area. The yield reduction ranges to 20 percent loss in higher - salinity areas. Some possible solutions, he said, may lie in more efficient irrigation systems such as drip irrigation; lining canals to reduce seepage; and installing subsurface drainage systems. "We need to study further what will be the effect if more fanners go to drip systems, trading their canal water for well Pumping," Gates said. Pueblo Chieftain / October 19, 2003 35