The Cowi and GFT engineering companies, in a joint company, have achieved a contract of $ 25.4 million to provide construction and construction services for the Irvine Ranch Siphon district Improvement Project in Orange County, California, the largest capital program in district history, according to the council’s records.
The expansion of $ 291 million will replace the existing prey of 59 feet with a new 136 -foot embankment dam and will increase the storage of recycled water from 578 acres to 5,000 acres. District officials say that the update, scheduled for completion by 2028, will strengthen the resilience of drought, reduce confidence in imported supplies and save customers about $ 85 million for 50 years.
“This is an important milestone for Cowi in the south of California,” said Arun Parsons, Vice President of Cowi North America, when announcing the contract on September 30. GFT is the entity received earlier this year, which was formed by the combination of Gannett Fleming Inc., Transystem Corp. and other firms.
Scope of expansion and supervision
District environmental files, reviewed by Enr, ask to demolish the current dam and build a 136 -foot embankment, increasing the ridge of 388 feet to 466 feet above sea level.
Planned improvements include a new slope, filtration drainage system, updated circulation works, and filtration and disinfection facilities at the footing. New access and maintenance roads will be built, along with wetlands and riparian mitigation.
A schematic map shows the project to improve the Sifon reservoir planned in Irvine, California, including the footprint of the new 136 -foot dam, proposed treatment facilities, spill, intake and starting work and flood area. Image courtesy of the Irvine Ranch/Eir Water District.
To strengthen public confidence, the district called for a independent design and security review box by 2021 of the mainly recognized prey engineers. They performed staged design reviews and visits to the site, issuing a closing letter in February, confirming that the concerns had been resolved and fulfilled the California’s Security Division.
The construction is expected to last two to three years. The district has not yet awarded a main contractor, although Aecom’s permission and design are complete. ESA is the environmental consultant that manages CEQA’s compliance.
To reduce community impacts, the district plans to restrict truck access during peak hours, limit most activities on weekdays and enforce dust and noise controls.
Long -term financing and value
Funded by an existing evaluation of capital facilities already included in property tax bills, the $ 291 million program will not increase drinking water rates, according to the district.
Federal support includes a prize of $ 12.25 million as part of the Watersmart program of the Bipartisan Infrastructure Act. In the financing announcement, the then Secretary of the Interior, Deb Haaland, said that the expansion of the Siphon reservoir “emphasizes the federal commitment to strengthen the resilience of the drought in California.”
The district projects long -term customers saving the water purchases imported from the north of California and the Colorado river. )[T]The Siphon deposit improving project is expected to save customers for approximately $ 85 million for 50 years, “said the district.
As the extended tank will allow almost 100% of the recycled water produced and reused, the increase in supply could be deployed during the summer months for irrigation, industrial refrigeration, dust control and fire suppression, improving the reliability of long -term water, said the district.
The district’s recycled water network covers 570 miles of “purple pipe” – the standard color of the industry used to distinguish non -polable water lines – and serves more than 6,200 water accounts or 28% of total deliveries.
Cowi has worked on other deposit projects and prisoners in California, such as Anderson Dam, Lafayette and Briones Reservoirs, Chabot Dam and Folsom Dam.
