Schaeffer Stream Crossings, Ponds, Water Diversion, and Micro-hydroelectric Power Project (Lake or Streamabed Alteration Agreement No. 1600-2020-0226-R1)

Schaeffer Stream Crossings, Ponds, Water Diversion, and Micro-hydroelectric Power Project (Lake or Streamabed Alteration Agreement No. 1600-2020-0226-R1)

The project site has multiple forms of water diversions including the impoundment of water in Pond1, diversion of water from Pond 1 for irrigation, a micro-hydroelectric power diversion, and the diversion of water from springs and small on-stream ponds into Pond 2. CDFW could only find one domestic use water right associated with Pond 2 (Application ID D030863) for non-consumptive aesthetic, recreational, and fish and wildlife preservation and enhancement use. The Water Board’s EWRIMS website shows two points with separate POD numbers that are located on Pond 2. No other water rights could be found that are associated with the impoundment of water in Pond 1, the diversion from Pond 1 for irrigation, or the micro-hydroelectric power diversion. The project is limited to nine encroachments. One encroachment has three components related to the existing on-stream pond, Pond 1. The first component is for water diversion from an on-stream pond on an unnamed tributary to the Russian River. Water is diverted for irrigation. Work for the water diversion will include use and maintenance of the water diversion infrastructure. The second component is the installation of a bypass flow structure in the southwest corner of the pond that will capture sheet flow entering the pond and direct it through a water pipe to the stream channel below the spillway. Work for the bypass structure will include installation of a redwood spring box to collect the water and trenching/installation of water lines connected to the spring box. The third component is the stabilization of a southwestern pond banks with appropriately sized rock armoring to reduce ongoing erosion. Another encroachment is for a separate existing on-stream pond (Pond 2) and has two components. Pond 2 receives water from a series of smaller existing spring and stream fed ponds. Water is directed through small, open concrete channels from the upper ponds to the larger pond below (Pond 2). The first component is the installation of a bypass flow structure at the inlet of the large pond in the southwest corner that will bypass water through a water pipe to the stream channel below the spillway. Work for the bypass structure will include installation of a redwood spring box to collect the water and trenching/installation of water lines connected to the spring box. The second component is the replacement of the existing, undersized, and failing spillway culverts. Work for this component will include excavation, removal of the failing culverts, replacement with new properly sized culvert, backfilling and compaction of fill, and rock armoring as necessary to minimize erosion. A third encroachment is for an existing micro-hydroelectric power diversion (POD-2) from an unnamed tributary to the Russian River. This encroachment has two components: 1) the non-consumptive diversion and 2) modification of the reentry point where water is discharged from the hydroelectric turbine. Water flows into a gravity-fed 4-inch pipe that is attached to a permanent, concreted, and screened structure located in the stream channel. The maximum proposed diversion rate from POD-2 for hydroelectric generation is approximately 50 gallons per minute (gpm). The existing season of diversion for hydroelectric generation is Jan. 1 – Dec 31 of each year, but water can only be diverted if Measures 2.85 to 2.91 below can be met. Currently, water exiting the hydroelectric turbine is discharged onto an upland location, flows over a dirt road, and spreads out preventing most of the water from returning to the stream channel. The second component is to install a new 23-foot long by 4-inch-wide discharge pipe on the turbine allowing the water to re-enter the stream directly adjacent to the turbine. To reduce erosion and scour of the stream channel by the discharging water, a new 8’ by 3’ rip rap apron using rock with a d-50 of 6 inches will be installed in the channel. The discharge pipe will be set in the channel at grade on the rip rap apron. A fish screen will be installed on the outlet of the discharge pipe to prevent wildlife from entering. Water is returned to the stream from POD-2 approximately 1,600 feet downstream. The six other proposed encroachments are to upgrade failing and/or undersized stream crossings. Work for five of these encroachments will include excavation, removal of the failing crossings, replacement with new properly sized crossings, backfilling and compaction of fill, and rock armoring as necessary to minimize erosion. The sixth stream crossing encroachment is an existing low water crossing with downcutting below the crossing on the edges of the banks. Work for this final encroachment will include excavation, re-contouring the banks to native slope to remove downcutting, and armoring the channel at the crossing with native rock sourced from the stream. All project activities (including bypass structures and micro-hydroelectric modification) shall require pre-construction surveys by a Designated Biologist if surface water is present one week before construction or becomes present during construction. Permittee disclosed additional features of interest. While some of the features are in good condition and meeting current performance standards, the September 17, 2020 site inspection revealed that some of the Table 2 features may need improvements. Existing stream crossings disclosed in the Notification, but not included as 1602 projects with fees, are not covered under this Agreement. If maintenance (such as armoring) and/or replacement become necessary, that work must be covered by a major amendment or a separate Notification.

Hopland

Mendocino

Northern California

Mendocino