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Intake work progresses under Lake Mead
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Southern Nevada Water Authority Photo
Workers stand Tuesday in a tunnel 600 feet underground near Lake Mead, where a new intake is being built to draw water from the reservoir.
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LAS VEGAS REVIEW-JOURNAL
LAS VEGAS REVIEW-JOURNAL
After a year of setbacks, the Southern Nevada Water Authority finally has some good news to report about its $700 million effort to build a new straw into Lake Mead.
Construction crews working 600 feet underground are now making "slow but steady progress" on a starter tunnel that was originally scheduled for completion a year ago, said Marc Jensen, director of engineering for the authority.
The tunnel is now about 310 feet long and roughly 50 feet from completion, Jensen said. If work proceeds at about 10 feet a week, it should be finished by next month.
Then the general contractor can begin lowering a massive digging machine into the ground for the largest part of the job, the excavation of a 23-foot tunnel through three miles of solid rock beneath the bottom of Lake Mead.
The tunnel-boring machine will be lowered in pieces and assembled underground, where it will eventually stretch the length of two football fields and weigh more than three Boeing 747 jetliners.
Jensen said the machine could be in place and ready to start digging by the end of the year.
And all it took to get things back on track was the largest change order in water authority history.
In February, the authority board agreed to add another $39.5 million to what was already the single largest construction contract the agency ever issued.
In exchange for the money, the project's designer and general contractor, Vegas Tunnel Constructors, accepted liability for any additional problems until the tunnel-boring machine is underground and chewing rock.
The change order also extended the timeline for the project by 593 days to the summer of 2014.
The 310 feet mined so far represents about 2 percent of the tunnel's total length.
"We still have a long way to go," Jensen said.
The Las Vegas Valley currently depends on two intake pipes to draw roughly 90 percent of its drinking water from Lake Mead.
The third intake will pull from deeper in the reservoir, allowing the flow of water to continue even if the lake shrinks enough to shut down one of the two existing straws.
The project is especially important to Henderson and Boulder City, which get all of their water from Lake Mead. As water authority chief Pat Mulroy put it, "Their plumbing doesn't connect to the rest of the valley."
Work on the third intake was already about three months behind on July 1, 2010, when a crew excavating the starter tunnel hit a fault zone, causing water and debris to flood the work area.
Vegas Tunnel Constructors spent weeks trying to stabilize the fault, but the area flooded again on Oct. 27 and Dec. 31.
The contractor eventually abandoned that tunnel and started excavating a new one in a different direction in hopes of skirting the troublesome fault line. So far, the tactic appears to be working, Jensen said.
The new starter tunnel is now more than twice as long as the old one.
To reach the work area, miners have to descend to the bottom of a vertical access shaft roughly the same height as a 55-story building. The tunnel-boring machine's sections will be lowered down the same shaft, which took more than a year to dig near the valley's two existing straws on the western shore of Lake Mead's Boulder Basin.
There are 130 people now working on the third intake, roughly 70 of them at the starter tunnel.
A crew of about 20 people are at the opposite end of the project, blasting a hole in the bottom of Lake Mead from a floating barge. The hole will eventually house a massive intake structure that will be lowered into it from the surface of the water.
Authority spokesman J.C. Davis said that part of the project remains on schedule.
The change order approved on Feb. 25 is the authority's largest in terms of pure dollars, but not by percentage.
That honor belongs to the River Mountains Water Treatment Facility, which was already being constructed in 2000 when authority officials decided to expand the design. The resulting change order totaled $31.3 million, or 21 percent of the project's total cost of $146.6 million.
The regional water agency also ran into cost overruns in the late 1990s during excavation work on its second Lake Mead intake.
That project was completed in 2000 but not before racking up change orders that increased the total cost from $68 million to $83 million.
Contact reporter Henry Brean at hbrean@reviewjournal.com or 702-383-0350.
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Contrary to statements made by Queen Mulroy, water is very politically manipulated. If you take a little time to read the data available thru BLM you can see that 2+2=1. The truth of Water is there isn't one. Thru-out history one fact has held the test of time. He who has the water rules.
This is not a "story" written by the typist at LVRJ. This is a positive spin press release published in the LVRJ for the benefit of the water authority and the Bumbling Bros. Inc. Engineering co.
"Only about 50' to go to be on schedule..." How about the real task of getting out under the main channel. We will still be reading these yarns in three years.
What they are not telling you is that the contractor is in hot water over OSHA/MSHA and Dept. of Labor violations. They also have a pending investigation on them from the EPA.
Its all a sham, Lake Mead will dry up eventually
Man Ive been eating hard boiled eggs all day and topped it off with asparagus for dinner. Can wait to go into the tunnel for a visit. Look out guys here I come!!
All the Injuns are doing doubles dealing blackjack and roulette at their casinos. Maybe thats the problem nobody availible to DO a rain dance.
The average water level for the lake is 1,173 feet. The top is 1,229. I think we got as low as 1,083. This year, with the heavy snows up North we are expecting about a 25 foot increase in water levels. Three more good years and we will be back to where we should be. Someone do a raindance
Re-arranging chairs on a sinking ship anyone ? Lake Mead is doomed, even though it received record water this year its still only at 46% capacity yet know one will pursue a real solution like desalination, yet we can dump 700 million into this project for a lake that could be empty in as soon as 10 year. Fools.....
Simple Solution: Bring water from Mexifornia on Harry Reid's Hi-Speed train to Victorville, then truck it in from there, drop it off at the MGM, then Monorail it to the closed Sahara. ----------------------- See, I have just as good ideas as the Southern Nevada Water Authority.
For the money they're wasting on this project they could have built 2 or 3 desalination plants in California, let them have that water and take an equal amount from their share of Colorado river water...
It would be cheaper to pay the no smoking/drinking/gambling californicators to go back to their own country.