Addendum - Dock Maintenance
The water in the lagoons and canals will remain at a level to support the aquatic wildlife. Residents, who require the water level to be lower than this to perform dock maintenance, will need to dam off their work area and use a pump to remove the remaining water.
Note that during the rainy season, whenever a one-day forecast predicts precipitation, the Lagoon water level will be changed from High Winter Level to Low Winter Level. The Lagoon will remain at the Low Winter Level until a clear two-day forecast, at which time it will be raised back to the High Winter Level. For more detail, please consult the Lagoon Management Policy.
When is the water lowered? The lagoon water will start to be lowered on the usual flush cycle.
When is the water filled? Provided that all dock work is complete by end of day Sunday, lagoons will begin to double-flush on Monday and refill to the appropriate seasonal level on Thursday.
If you have any questions, call the Department of Public Works at 415-927-5057.
||Walk High and Low Canals and remove any debris and note any possible concerns/anomalies
||Drain High Canal
||Drain Lagoon 1, Marquart Lagoon, and Pixley Lagoon *
||Fill Lagoon 1, Marquart Lagoon, and Pixley Lagoon to prescribed levels
||Confirm lagoons are at prescribed levels
* On Wednesday, the automatic gates at High Canal Pump Station are set to the summer mode to allow water - incoming tide - into the High Canal to a predetermined level (2.0 ft). When that level is reached, the gates close. In turn, the water from the replenished High Canal drains into the three lagoons. When the High Canal drops to a level of 0.0 ft, the gates reopen and repeat the cycle. On the next out-going tide, the gates open and remain so until the next in-coming tide.
This protocol allows for a more robust flush of the lagoons. In order to avoid overfill at Lagoon 1, we close 2-3 of the “outside” flap gates so that water can enter from only the three remaining gates. All of the six inside gates remain open so that all water that has entered the lagoon drains back into the High Canal. On Thursday, we change the mode of High Canal to “summer” so that we attain the prescribed summer levels. Marquart Lagoon is automated, and barring a malfunction, it is not a concern. Pixley Lagoon is small and not automated, so we monitor the fill rate.