A Provost & Pritchard-led project to filter chemical compounds out of the Bakersfield water system has garnered statewide awards, and a chance at a national accolade. Image via Provost & Pritchard
Written by Donald A. Promnitz
A Fresno-based engineering firm has continued to garner praise and recognition for its involvement in improving the quality of drinking water for the people of Bakersfield — and now other towns in the Valley are following suit.
According to Kevin Berryhill, principal engineer for Provost & Pritchard Consulting Group, the issue began in 2016-17, when the state rolled out new drinking water quality regulations, limiting the legal amount of 1,2,3-Trichloropropane (TCP), a chemical compound known to have carcinogenic properties. Provost & Pritchard approached the City of Bakersfield in in 2016 and began doing study work that October. The following July, they received clearance from the city.
“The city got ahead of it,” Berryhill said. “They were one of the few utilities that started acting on this quickly enough to put something in place, to find a solution before they went out of compliance.”
Provost & Pritchard got to work on designing 34 water treatment plants over the course of a year. However, a short deadline (about a year) meant that their team had to design the project as construction was ongoing. The Bakersfield office of Provost & Pritchard was also heavily involved, with senior engineer Jeane Hill managing the overall project.
The treatment plants, Berryhill said, work by moving the water through a coarse powder made of carbon. The TCP in the water is then bonded to the carbon — a process called “adsorption” — and moved along with the chemical removed. This carbon will then be hauled off and heated in a kiln. Once the TCP is burned off, the carbon can then be reused. The amount of water that can be filtered varies from plant to plant, but on average, this amounts to around 1,000 gallons a minute.
The task of constructing the plants fell on W.M. Lyles Co.’s office in Bakersfield. The contract amount for the work was more than $29 million, which was brought up to a combined total of $41 million.
At the same time, the aggressive timetable meant the Lyles/Provost team had to assist the city with procuring the vessels and carbon needed for the job during the first few months. According to Rick Amigh, Lyles Construction Group president and CEO, six staff personnel were contracted for the project, directing more than 60 field crewmembers working to build the plants.
“I have been involved in the construction industry for almost 40 years and this project was one of the most challenging projects for W. Lyles Co. to manage and construct,” Amigh said. “It was only through the teamwork of all the stakeholders involved that the project was a success.”
The efforts of Provost & Pritchard have also gained attention on the state and national level of the engineering community. So far, they’ve received accolades from the American Society of Civil Engineers, the American Public Works Association and the American Council of Engineering Companies. In the latter’s case, they’ve taken the regional award covering Southern California, qualifying them for the nationals next week. Normally, they may have been nominated for the 2018 awards, but minor work had to be done on the plants, a technicality that pushed their eligibility to 2019.
Meanwhile, Bakersfield isn’t alone in seeking help from Provost & Pritchard on the issue. Currently, Berryhill says the firm is working with Tulare, Kingsburg, Fresno and other cities to make treatment plants.
Under the new California regulations, drinking water is only able to have 5 parts of TCP per trillion, but eventually, the state has a goal of lowering it to .7 parts. Berryhill, however, says his team aims to stay ahead of this.
“And generally when we design these projects, we design it to get it all out,” Berryhill explained. “As low as you can detect it, we want to get it out.”