That Damn Dam Damage!
“Better safe than sorry.” “Better late than never.” These are some of the phrases uttered in regard to the rebuilding of the Tempe Town Lake Dam. It’s being delayed, which means the likelihood of completion by Ironman Triathalon time in November is unlikely. Wanna know why? Read on…
(Courtesy of Dianna M. Náñez – Arizona Republic)
The state water agency charged with Arizona’s non-federal dam safety has put the replacement of the Tempe Town Lake dam on hold until the agency can feel confident the new dam will be safe.
Michael Johnson, assistant director and chief engineer of the Arizona Department of Water Resources, said Tempe must give the department a plan for investigating the cause of the dam’s failure and an updated timeline for construction of a new dam on the west side of the lake. The city agreed to do so.
Johnson said his agency might allow construction to begin before the investigation is complete if it feels confident that the new dam will be secure. Johnson was part of a team of more than a dozen experts who inspected the broken dam Tuesday along with Tempe city officials. He noted it was fortunate that nobody was killed when the dam that had been deteriorating for years burst.
“Dam failure can lead to injury, loss of life and property and infrastructure damage downstream. Our job is to prevent those things from happening,” he said.
He would not speculate on whether the decision to put construction on hold would affect the city’s goal of reopening Town Lake by November. He said Tempe officials told him they would submit a plan for the investigation and construction within a few days.
The Tuesday inspection and a meeting that followed were attended by several entities that have a stake in the dam.
Representatives from PCL Construction Inc., the company that was contracted to replace the dam, were present. Also attending were engineers from Bridgestone Industrial Products Inc., the manufacturer of the dam that ruptured and the replacement dam; and officials from Stantec Consulting, the engineering and construction consultant for the dam replacement.
Among the Tempe officials inspecting the deflated rubber dam was Assistant City Manager Jeff Kulaga.
Johnson said everyone at the site was acutely aware that the timing of the dam rupture, which failed at 9:46 p.m. on July 20, saved lives.
When the dam burst, an explosion of rubber could be heard, emergency-warning sirens sounded and water hurled west down the Salt River bed. Had it ruptured the next morning, when the state water agency had approved Tempe sending teams of workers to the west wall of the dam to begin replacing the deteriorating rubber dams, someone likely would have been killed, officials have agreed. “I think the timing was fortunate . . . it could have been a whole different situation,” said Don Darden, a Bridgestone spokesman.
Tempe had planned to replace the deteriorating dam that failed with a new set of four rubber dams on loan from Bridgestone. Within five years, as per a legal agreement with Bridgestone, Tempe would remove the temporary dam and install a permanent one.
Despite the setback, Kulaga said Tempe still hopes to have the new dam in place and the lake filled by November in time for the Ford Ironman Arizona triathlon and other activities hosted at the lake that attract much-needed tourism dollars for the cash-strapped city.
“We look forward to cooperating with (the state agency) with regard to safety of the dam and the water resources involved,” he said. “I think based on our meeting, we can confidently move toward that (November) timeline.”
Johnson said the officials attending Tuesday’s meeting understood that meeting that goal of restoring Town Lake depends on how quickly the investigation into the dam failure unfolds.
“I think everybody’s on the same page about safety,” he said.
Johnson said no one would know for certain why the dam failed until its sections are moved to a warehouse for closer inspection.
Darden said Bridgestone hopes Tempe will allow the company’s engineers to analyze the ruptured dam.
“It will need a thorough investigation, and certainly we want to be a part of that,” he said.
While the officials and experts walked the dam wreckage Tuesday, Bill Curry, a retired Tempe resident who walks the lake almost daily, peered down at them. He hoped that the groups involved in restoring Town Lake don’t get sidetracked.
“My worry is that politics and the lawyers that are going to come into this . . . don’t interfere with getting the lake back up,” he said. “I watched them build it. I want to see it filled again.”