restoring streams to restore the bay

by Julian Meisler

If you’ve hiked or driven past the uplands of Sears Point, located just north of Highway 37, then you’ve seen the open grasslands, perhaps the wildflower fields — and you’ve definitely seen the large eroded drainages.
 
Sears Point has roughly nine miles of creeks or drainages that flow seasonally. The erosion that you see is the result of a long history of land use that has included heavy cattle stocking rates on a landscape that is steep and naturally prone to erosion. The flat grasslands in the foreground were once part of the San Pablo Bay tidal marshes. Streams would have flowed from the hills into the marshes, bringing sediment to sustain their growth. As we all know, that changed long ago.
 
While some of the eroded drainages are more like canyons and have little hope for true restoration (the ends don’t justify the means), we can slow their erosion with changes in management. Other drainages are not so far along and offer outstanding opportunities for restoration and enhancement.  

​While much of my time over recent years has been spent on tidal restoration, our part-time staffer and full-time Berkeley graduate student has spent many hours walking these drainages as the subject of his thesis. His ponderings and findings are quite interesting — far more than I can relate here. But his ideas for stream restoration are spot on and the timing is good as we are focusing a lot of attention on it now. 

​Restoring streams and reconnecting them to the bay is a primary recommendation of the recently released report and action plan entitled The Baylands and Climate Change. In fact, it’s an update to the 1999 Baylands Ecosystem Habitat Goals Report, which has guided much of our work in the Baylands over the past 15 years. 
 
Here’s the gist. Since the Gold Rush and its associated hydraulic mining activity, the bay has been full of sediment (and, at times, overstuffed). That sediment has built and nourished new and existing marshes. Over the past 20 years, the sediment supply has dwindled and it has become increasingly important to derive sediment from local watersheds. At Sears Point and in many areas of the North Bay, streams no longer flow to the bay. They flow through ditches to massive pumps, which then shunt the water into the bay. It’s not the worst thing — but it definitely could be improved. 

​Restoring tidal marshes is paramount — and restoring streams that drain to marshes is a key step of this process. Restoration of several miles of Tolay Creek, which used to drain to the bay, is well underway. Over the next few years, we hope to build on that by restoring miles of priority streams at Sears Point. Stay tuned for updates and opportunities to get involved.  

Julian Meisler is Sonoma Land Trust's Baylands Program Manager.