Improving the way Rinconada removes solids during the water treatment process gets a big boost in August when two new gravity thickeners come online at the treatment plant.
These structures will replace eight settling basins and use land currently needed for the existing thickening process. Under this interim practice, the thickeners will allow the plant to continue operating while a centrifuge pump station and mechanical dewatering system and load out structure are built. This will increase dependability with a redundant system to avoid unplanned outages and free up valuable space for the upcoming Reliability Improvement Project.
The work also eliminates a labor intensive process for handling solids at the plant by using a drive-through loading operation to carry solids directly into a trailer for hauling. Under the previous process, a full-time operator had to run a loader to relocate the solids from a single pile to a staging area, where a loader again handled the material and placed it into a trailer. The same person had to move settled sludge with from one end of the thickening basins to the intake on the other end and manually operate valves off the eight settling basins.
Under this new process, Rinconada can remotely monitor the system so an operator can view its operation from the main control room. The new equipment allows the district to continue producing a daily average of 7,000-pounds, with a peak production of more than 16,000 pounds of sludge without having to shut down for maintenance, unlike the current system.
About 20 percent of this project is complete, with upgrades to reservoir valves and the chemical storage wall footing. When the plant shuts down in November and January 2015 for regular maintenance, crews will finish work on the treated water valves and West Pipeline flow meter. No customers will be out of water during that shutdown. Once the new process is in full operation, the final work on the project will involve demolishing the mechanical equipment in the old belt press building and removing several obsolete structures and equipment. The district will also build a service road to accommodate ongoing construction traffic while the plant continues to operate.
The water district expects to complete the entire project by January 2016 in the midst of start-up construction for the Reliability Improvement Project.