Winter Means Less Water Demand and Best Time to Do Plant Maintenance

At the District, late fall and early winter are when we usually see a decline in water demand. Our Maintenance and Operations teams take advantage of this time period to perform preventive maintenance on various aspects of our our plant essential to providing water.

Drain and Wash Down of Sedimentation Basins
Our Wylie Complex has four water treatment plants with a total of 22 sedimentation basins that need to be drained one by one for annual maintenance. These basins are where raw lake water is rapidly mixed with ferric sulfate in order to force suspended particles to sink to the bottom. After draining, our Facilities Services crews wash down the sediment that has built up during this process (called flocculation). Once a basin has been washed down, the Technical Services crews can safely enter and make necessary repairs or adjustments to the mechanics and mixing paddles themselves.

New Paddles Installed
Three of the four plants in the Wylie complex use paddles for the sedimentation process that were designed with California Redwood. In an effort to be more environmentally friendly, prolong the life of the paddles and reduce cost of repairs, the District has begun to transition to using Fiberglass Reinforced Polymer (FRP) paddles. The new paddles have a 10- to 15-year lifespan and made of a light material, reducing the stress on other mechanical components.

Electrical Maintenance
While the plant is out of commission, the Electrical department will coordinate the preventive maintenance of the electrical switchgear. This switchgear is vital to maintaining power to the plant. Ensuring that the components are in proper working order will reduce failures during peak demand and will also reduce electric consumption.

A Coordinated Effort
Winter maintenance is a team effort, and it must be coordinated with several departments. Every precaution is taken to ensure that all members of the team are safe. Every week a shutdown coordination meeting is held with the maintenance, operations and engineering departments to ensure the maximum amount of work gets completed while the plants are offline.