The unnamed intermittent channel in the drainage is approximately 2 miles long and extends from the Solano Wind Project Operations and Maintenance buildings, located along Toland Lane near the intersection with Montezuma Hills Road, downstream to its confluence with the Sacramento River. The channel completely dries out during the late spring or early summer and remains dry until the wet season. The drainage is currently populated by trees, many of which are large and centered in the channel, and areas of dense shrub thickets that disrupt the flow of water and cause erosion along the channel banks.
SMUD proposes to mow, prune, and remove riparian vegetation from an unnamed drainage along the eastern boundary of the Solano Wind Project to improve water conveyance, decrease erosion.
The work would include mowing/cutting numerous thickets of Himalayan blackberry (Rubus americanas) and one relatively small area of riparian scrub composed of sandbar willow (Salix exigua). Up to 30 percent of riparian tree canopy may be pruned. The vegetation is located within the bed and along the banks of the channel, which extends approximately 2.2 miles (11,800 feet) from the upstream end near the SMUD operations center to the downstream confluence at the Sacramento River. The project also involves relocating a fence on the McCormack parcel to the southwest side of the drainage from the McCormack parcel to SMUD property.
All mowing/cutting would occur from outside the channel on current access roads and uplands adjacent to the channel. No heavy equipment would be allowed within the channel or on its banks below the ordinary high-water mark or in areas that would cause erosion. Vegetation would be removed from the channel and banks with long arm/reach equipment that extends into the channel to carefully mow/cut and move the vegetation to the adjacent upland zone for processing. Up to 30% of the tree canopy along the channel may be pruned using chainsaws or similar devices from a bucket truck or by tree crews climbing the trees. All work will be performed in the dry season when the channel is dry.
Work would be limited in the downstream reach of the channel, from the Sacramento River to 650 feet upstream of the Sacramento River, subjected to perennial tidal influence to avoid impacts to aquatic resources and because the banks in this reach are steep and incised near the confluence. In these areas, no vegetation removal would occur at or below the high tide line or in emergent marsh that extends above or upslope of the high tide line. Likewise, areas of freshwater emergent marsh (tule and cattail) upstream of the tidal zone and in the upper extent of the channel near the operations and maintenance facility would be flagged as sensitive natural community/habitat areas and avoided.
Work is expected to occur every other year between August 15 and October 15 starting in 2022. Work will be repeated in 2024 and 2026.