2017-22533. Notice of Amended Application Tendered for Filing With the Commission and Establishing Procedural Schedule for Licensing and Deadline for Submission of Final Amendments; Turlock Irrigation District and Modesto Irrigation District, ...

Take notice that the following hydroelectric application has been filed with the Commission and is available for public inspection.

a. Type of Application: New Major License.

b. Project No.: 2299-082.

c. Date Filed: October 11, 2017.

d. Applicant: Turlock Irrigation District and Modesto Irrigation District, California.

e. Name of Project: Don Pedro Hydropower Project.

f. Location: The Don Pedro Project is located on the Tuolumne River in Tuolumne County, California. Portions of the project occupy public lands managed by the Bureau of Land Management.

g. Filed Pursuant to: Federal Power Act, 16 U.S.C. 79 (a)-825(r).

h. Applicant Contacts: Steve Boyd, Turlock Irrigation District, 333 East Canal Drive, Turlock, California 95381-0949, [phone]; and Anna Brathwaite, Modesto Irrigation District, P.O. Box 4060, Modesto, CA 95352, [phone].

i. FERC Contact: Jim Hastreiter at [phone] or [e-mail].

j. This application is not ready for environmental analysis at this time.

k. The Project Description:

Don Pedro Dam and Reservoir

The primary project feature is Don Pedro Dam, a 1,900-foot-long and 580-foot-high zoned earth and rockfill structure. The top of the dam is at elevation 855 feet mean sea level (msl).

Don Pedro Reservoir extends upstream for approximately 24 miles at the normal maximum water surface elevation of 830 feet (msl). The surface area of the reservoir at the 830-foot elevation is approximately 12,960 acres and the gross storage capacity is 2,030,000 acre-feet.

Don Pedro Spillway

Don Pedro Spillway is divided into two sections, one gated and one ungated, located immediately adjacent to one another in a saddle area west of the main dam. The gated spillway section is 135-feet-long, with a permanent crest elevation of 800 feet, and includes three radial gates each 45 feet wide by 30 feet high. The ungated spillway is an ogee section 995 feet long with a crest elevation of 830 feet msl and a top of abutment elevation of 855 feet msl. The spillway capacity at a reservoir water level of 850 feet msl is 472,500 cubic feet per second (cfs). Flow releases over the ungated ogee-crest section of the spillway have occurred only once since project construction, in early January 1997. Flows at the spillway are released to Gasburg Creek, which in turn flows into Twin Gulch, and then back into the Tuolumne River approximately 1.5 miles downstream of the main dam.

Outlet Works

The project facilities include a set of outlet works located at the left (east) abutment of the main dam. The outlet works consist of three individual gate housings, each containing two 4-feet-by-5-feet slide gates. The outlet works are situated in a 3,500-foot-long concrete lined tunnel that originally served as the water diversion tunnel during project construction. The inlet to the tunnel has an invert elevation of 342 feet msl and the outlet, which is located approximately 400 feet downstream of the powerhouse, has an invert of 310 feet. At a reservoir water surface elevation of 830 feet msl, the total hydraulic capacity of the outlet works is 7,500 cfs.

Power Intake and Tunnel

Flows are delivered from the reservoir to the powerhouse via a 2,960-foot-long power tunnel located in the left (east) abutment of the main dam. The tunnel transitions from an 18-foot 6-inch concrete-lined section to a 16-foot steel-lined section. Emergency closure can be provided by a 21-foot-high by 12-foot-wide fixed-wheel gate that is operated from a chamber at the top of the gate shaft. Flows from the power tunnel are delivered to the four-unit powerhouse and a hollow-jet control valve in the powerhouse.

Powerhouse

Located immediately downstream of the main dam, the Don Pedro powerhouse contains four turbine-generator units and a 72-inch hollow jet valve. The reinforced-concrete powerhouse is 171 feet long, 110 feet high and 148 feet wide. It houses four Francis turbine generator units with a nameplate capacity of 168 megawatts (MW) and a maximum output at optimum conditions of approximately 203 MW. Combined hydraulic capacity of the four units under maximum head is approximately 5,500 cfs.

The powerhouse also contains a 72-inch hollow jet valve located in the east end of the powerhouse with a centerline elevation at discharge of 299 feet msl. The hydraulic capacity of the hollow jet valve is 3,000 cfs. While turbine Units 1 through 3 discharge directly to the river channel, Unit 4 discharges to the outlet works tunnel approximately 250 feet upstream of the tunnel outlet. Water to Unit 4 is delivered through a bifurcation from the hollow jet valve pipe. With Unit 4 in operation, the hollow-jet valve capacity is reduced from 3,000 cfs to 800 cfs. The powerhouse tailwater during turbine operation varies from a low elevation of about 298 feet msl to a high elevation of about 303 feet msl under normal operating conditions. The tailwater elevation at the outlet works tunnel is approximately 300 feet msl.

Switchyard

The project switchyard is located atop the powerhouse at elevation 340 feet msl. The switchyard provides power delivery and electrical protection to the Districts' transmission systems. The switchyard includes isolated phase buses, circuit breakers, and four transformers that raise the 13.8 kilovolt (kV) generator voltage to 69 kV transmission voltage.

Gasburg Creek Dike

Don Pedro dam spillway discharges into Gasburg Creek. Gasburg Creek dike is located near the downstream end of the spillway, and directs flows from Gasburg Creek into Twin Gulch where spillway discharges join the Tuolumne River approximately 1.5 miles downstream of the Don Pedro powerhouse. Gasburg Creek dike consists of an impervious earth and rockfill dam approximately 75 feet in height, with a slide-gate controlled 18-inch-diameter conduit. The top of Gasburg Creek dike is at elevation 725 feet msl.

Dikes A, B, and C

The project includes three small embankments—Dikes A, B, and C—constructed in low saddles on the reservoir rim with top elevations of 855 feet msl. Dike A is located between the main dam and spillway. Dikes B and C are located east of the main dam.

Recreation Facilities

The project has three developed recreation areas, Fleming Meadows, Blue Oaks, and Moccasin Point. Primitive and semi-primitive lakeshore camping occurs on much of the rest of its shores. The project provides both floating and shoreline restrooms in addition to those at the developed recreation areas. Facilities also include hazard marking, regulatory buoy lines, and other open water-based features including houseboat marinas and a marked water-ski slalom course.

l. Locations of the Application: A copy of the application is available for review at the Commission in the Public Reference Room or may be viewed on the Commission's Web site at http://www.ferc.gov using the “eLibrary” link. Enter the docket number excluding the last three digits in the docket number field to access the document. For assistance, please contact FERC Online Support at [e-mail], [phone] (toll free), or [phone] (TTY). A copy is also available for inspection and reproduction at the address in item (h) above.

m. You may also register online at http://www.ferc.gov/​docs-filing/​esubscription.asp to be notified via email of new filings and issuances related to this or other pending projects. For assistance, contact FERC Online Support.

n. Procedural Schedule: The application will be processed according to the following preliminary Hydro Licensing Schedule. Revisions to the schedule may be made as appropriate.

Milestone	Target date
Notice of Acceptance/Notice of Ready for Environmental Analysis	October 2017.
Filing of recommendations, preliminary terms and conditions, and fishway prescriptions	December 2017.
Commission issues Draft Environmental Impact Statement (EIS)	July 2018.
Comments on Draft EIS	September 2018.
Modified Terms and Conditions	November 2018.
Commission Issues Final EIS	February 2019.

o. Final amendments to the application must be filed with the Commission no later than 30 days from the issuance date of the Notice of Ready for Environmental Analysis.

Dated: October 12, 2017.

Nathaniel J. Davis, Sr.,

Deputy Secretary.