erosion

November Visit (11/30/2016)

Image | | robinleecarlson

In November, on a cool but not cold day, I hiked to the top of Blue Ridge.  Looking out at Lake Berryessa, it was easy to see part of the area burned by the Cold Fire last summer.

berryessaview_2016nov30_sm

On the way up the trail, I looked for mushrooms enjoying the damp left by rains earlier in the month, and observed regrowth of mountain mahogany (Cercocarpus betuloides), blue oaks (Quercus douglasii), and chamise (Adenostoma fasciculatum).  The leaves of yerba santa (Eriodictyon californicum) along the trail were losing their waxy coating.  The waxy coating, presumably beneficial in retaining water during dry months, is resinous and highly flammable.  Yerba santa seeds may require fire to germinate and can also resprout from rhizomes following fire.

hikingup_2016nov30_sm

Hillsides stripped of their erosion-controlling vegetation by the fire have been shored up with erosion matting installed by Tuleyome and Friends of Stebbins Cold Canyon Reserve.

restoration_2016nov30_sm

Looking across Cold Canyon I was struck by the “rivers” of dead tree branches running down the canyons of Pleasants Ridge.  They made a ghostly grey against the greens of new growth and the hills still mostly yellow from the summer.

pleasantsridge_2016nov30_sm

 

blueridge_2016nov30_sm

A few mid-action photos:

Water Quality (12/30/2015 & 1/8/2016)

Image | | robinleecarlson

High-intensity chaparral fires cause increased erosion and sediment transport into streams, and this can be seen in the thick black sludge filling the Cold Creek channel.  On my December visit, with no recent rain, the creek bed was pretty dramatically full of sludge.

December 30, 2015:

coldcreek_30dec2015_sm

By my January visit, several small storms had contributed to small flows in the creek.  As water washes the runoff from the burned hillsides through the system, ash from the fire as well as contaminants that were present on the hillsides will move through Cold Creek and into Putah Creek.  This creates water quality concerns which will be addressed by future water quality monitoring to be conducted by the Solano County Water Agency.

January 8, 2016:

coldcreek_8jan2016_sm