The Southern Nevada Water Authority’s largest single contract to date just got a little pricier. Photo: Tony Illia For ENR Drier days Workers in 2010 in staging vault that later flooded twice. Photo: Tony Illia For ENR Tunnel-boring machine head will drill for three miles. A starter tunnel for a third raw water intake at Lake Mead flooded three times in six months last year, prompting its contractor, Vegas Tunnel Constructors LLC —a joint venture of S.A. Healy Co., Lombard, Ill., and Impreglio S.p.A., Sesto San Giovanni, Italy—to drill in a drier direction. Costs for the design-build project, awarded in
Turkey is proposing a major dam-building program, proposing at least 18 new dams along its borders. The government claims the multiyear, multimillion-dollar infrastructure initiative would ease tensions over water-sharing, prevent flooding, irrigate farmland and generate electricity. On Feb. 6, Turkish Prime Minister Recep Tayyip Erdogan and Syrian Premier Naji al-Otari broke ground for the Dostluk Baraji, or Friendship Dam, on the Orontes River, which flows from Lebanon into Syria and Turkey. The dam, 580 meters long and 14.5 m high, is designed to create a reservoir large enough to store 115 million cu m of water. At an estimated cost
The San Francisco Public Utilities Commission is seeking a contractor to replace the 85-year-old Calaveras Dam near Fremont and Sunol in the East Bay for a project estimated to cost $434 million. Photo: Courtesy of SFPUC The Calaveras Dam normally supplies nearly half the water to the Bay Area. Notice went out on Jan. 31, with a pre-bid meeting scheduled for Feb. 15 and contract award at the end of March. Construction, estimated to cost between $250 million to $300 million, is set to start in the summer. Prequalified prime contractors eligible to bid on the project include Dragados USA,
When Indianapolis Mayor Greg Ballard came into office in 2008, he inherited a wastewater treatment and sewer system that was averaging 7.8 billion gallons of overflow each year, according to federal officials. At the time, it was not unusual for as little as one-quarter to a half inch of rainfall to fill the combined sewers to capacity and flood raw sewage into local rivers and streams. Ballard also inherited a two-year-old consent decree with the U.S. Dept. of Justice to bring the city in compliance with the Clean Water Act as well as a project to expand its wastewater treatment
A draft California Public Health Goal could lead to a requirement for California water agencies to reduce hexavent chromium to the ultra-low level of 0.02 parts per billion. The naturally occurring suspected carcinogen is present in as much as a third of the state’s groundwater supply. The federal government currently only regulates total chromium levels at 100 parts per billion. The draft goal, released in December 2010, was reduced from a previously suggested 0.06 parts per billion “to account for increased sensitivity associated with early-in-life exposures,” according to a state study. The California Dept. of Public Health could set drinking-water
By April, the power will go on in the $1.4-billion, 2-billion-gallon-per-day Catskill/Delaware Ultraviolet Disinfection Facility, the world�s largest. The plant is being built by the New York City Dept. of Environmental Protection in a county to the north to deliver safe drinking water to the city�s nine million residents. By April, the power will go on in the $1.4-billion, 2-billion-gallon-per-day Catskill/Delaware Ultraviolet Disinfection Facility, the world’s largest. The plant is being built by the New York City Dept. of Environ-mental Protection in a county to the north to deliver safe drinking water to the city’s nine million residents. “We are
The California Coastal Conservancy reached agreement in December to bypass an obsolete dam on California�s Carmel River rather than dredging and buttressing the 90-year-old structure. The $84-million reroute and dam removal project will divert the river around the 106-ft high concrete arch San Clemente Dam built in 1921. The basin has since been swamped with 2.5 million cu yds of sediment, thereby reducing storage capacity from 1,425 acre-ft to 125 acre-ft. In 1992, the California Dept. of Water Resources Division of the Safety of Dams issued a safety order because of possible failure from a maximum flood event or an
What easily could have been a run-of-the-mill sewer pipeline replacement project in Oregon went from underground to underwater—creating what participants say will be the world’s first buoyant gravity line. Photo: Brown And Caldwell Pipeline under construction in Lake Oswego, Ore., will be the world’s first buoyant-gravity line when completed next April. Now under construction, the Lake Oswego interceptor sewer boasts 17,000 ft of wastewater-carrying pipe and another 12,000 ft of attached air-filled buoyant pipe. Replacing an existing submerged concrete pile-supported pipeline built in 1963, the new system will hook to the city’s current system on both sides of the lake.
On Dec. 15, the California Natural Resources Agency, U.S. Dept. of the Interior and four other agencies released the Bay Delta Conservation Plan, calling for construction of a $13-billion tunnel to bring water from northern California to the Central Valley. Large Image The multi-agency study looked at alternatives to the 100-year-old delta levee system that would preserve water shipments to the southern part of the state without damaging the delta ecosystem and killing fish. Studies point to the intake pumps in the San Francisco Bay Area as a primary source of large-scale fish mortality in the region. “The current infrastructure
Within a few seconds in mid-December, engineers at a new research facility in Vicksburg, Miss., sealed a 2,000-cu-ft-per-second torrent of water pouring through a 40-ft-wide, eight-ft-deep levee breach using a 100-ft-long, 15-ft-dia., air- and water-filled fabric tube rolling in the stream. Photo: Angelle Bergeron For ENR Full-scale trials of a 100-ft-long levee plug at a new test facility in Vicksburg show technology and techniques for rapidly sealing levee breaches are ready for business, but funds are lacking. Graphic: Courtesy ERDC A 2.2-million-gal source pool and collapsible weir on the test basin simulate a breach. Related Links: Ready To Roll: Levee