In 2023, District staff were thrilled to offer water customers a full, unallocated irrigation season after several years of drought. However, the season was not without its challenges, and one of the most trying developments was an explosive growth of algae and aquatic weeds. The extreme profusion of aquatic weeds formed masses that clogged the headgates at the Winters and West Adams Canals. The matted weeds prevented water from entering the canal system and caused water shortages, blocked trash racks throughout the canal system and clogged water users’ pumps.
In response to this development, the District’s operational staff cleaned the trash racks at the headgates two to three times per day. Often, this meant that during the hottest part of the day, staff headed out to hoist pads of matted aquatic weeds and algae with large, curved pitchforks off of the trash racks to allow water to flow into the canal. Although cleaning the trash racks several times per day, seven days per week mostly kept the water flowing at a satisfactory rate, the weeds and algae still posed problems for growers’ pumps, and clogged trash racks within the delivery system. The abundance of weeds in the canals required additional herbicide treatments, which caused the District to exceed its chemical budget by nearly $40,000, while also incurring additional labor costs.
Although the District has always contended with a fair bit of algae and aquatic weeds due to the high nutrient content of Clear Lake source water, 2023 was the most challenging to date. It became clear that the District needed more sustainable solutions to the problem. In search of solutions, Operations and Maintenance Supervisor Sal Espinoza looked to Aqua Systems 2000. Aqua Systems 2000 has been an excellent partner with the District as a supplier of irrigation control gates that the District has installed at key locations in the distribution system. Aqua Systems 2000 also designs trash management systems for water systems throughout the United States and Canada.
Aqua Systems 2000 has proposed a system that consists of metal arms called trash deflectors that direct the flow of water to a vertical conveyor that lifts weed and algae out of the water and dumps it onto a horizontal conveyor belt onto a disposal pile. The District’s Board of Directors approved the proposed solution at the February board meeting after a presentation by Supervisor Espinoza, and the system is scheduled to be installed during the month of March.
Although the weed removal system will go a long way in combatting the weed problem and help to cut down on labor and herbicide costs, while also helping to protect District employees against the risks of heat exposure and musculoskeletal injuries, it is not expected to be a complete solution. Supervisor Espinoza still expects that there will be a need to control algae and weeds downstream of the headgates and is currently investigating innovative and cost-effective ways to better serve District water customers.