Document ID: FERC-2023-0624-0001
Agency: ferc
Document Type: Notice
Title: Application: Seattle City Light
Posted Date: 2023-05-16T04:00Z

[Federal Register Volume 88, Number 94 (Tuesday, May 16, 2023)]
[Notices]
[Pages 31261-31262]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-10357]

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DEPARTMENT OF ENERGY

Federal Energy Regulatory Commission

[Project No. 553-244]

Seattle City Light; Notice of Application Tendered for Filing 
With the Commission and Establishing Procedural Schedule for Licensing 
and Deadline for Submission of Final Amendments

    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.: 553-244.
    c. Date Filed: April 28, 2023.
    d. Applicant: Seattle City Light (City Light).
    e. Name of Project: Skagit River Hydroelectric Project (project)
    f. Location: The existing project is located on the Skagit River, 
in Whatcom, Snohomish, and Skagit Counties, Washington. The project 
occupies Federal lands under the jurisdiction of the National Park 
Service and the U.S. Forest Service.
    g. Filed Pursuant to: Federal Power Act, 16 U.S.C. 791 (a)-825(r).
    h. Applicant Contact: Chris Townsend, Director of Natural Resources 
and Hydropower Licensing, Seattle City Light, P.O. Box 34023, Seattle, 
WA 98124; telephone (206) 304-1210.
    i. FERC Contact: Matt Cutlip, (503) 552-2762 or 
[email protected].
    j. This application is not ready for environmental analysis at this 
time.
    k. The Project Description: The project consists of three 
hydroelectric developments (i.e., Ross, Diablo, and Gorge), a 
transmission line corridor that is about 100 miles long containing 
multiple transmission lines, two company towns (i.e., Newhalem and 
Diablo), and numerous recreation and interpretive facilities. The 
project also includes 10,803.4 acres of fish and wildlife mitigation 
land.
    The Ross Development is located at river mile (RM) 105.1 on the 
Skagit River and consists of: (1) a 540-foot-high, 1,300-foot-long 
concrete arch and gravity dam with two spillways, each of which has six 
20-foot-high, 19.5-foot-wide radial tainter gates, two butterfly valves 
at an elevation of 1,346.2 feet, and two jet valves at elevations of 
1,275.2 and 1,260.2 feet; (2) the 11,725-surface-acre Ross Lake with a 
storage capacity of 1,432,000 acre-feet at normal maximum water surface 
elevation of 1,608.76 feet; (3) two bifurcated intake structures with 
four 20-foot-wide, 198.13-foot-long openings and trashracks; (4) one 
1,800-foot-long and one 1,634-foot-long, 24.5-foot-diameter concrete-
lined power tunnels; (5) four 16-foot-diameter, 350-foot-long 
penstocks; (6) a powerhouse containing four generating units with a 
total authorized installed capacity of 352.5 MW; (7) two 230-kilovolt 
(kV), 3.8-mile-long transmission lines extending from the power plant 
to Diablo Switchyard; and (8) appurtenant facilities.
    The Diablo Development is located at RM 101.2 on the Skagit River 
and consists of: (1) a 389-foot-high, 1,180-foot-long concrete arch and 
gravity dam, with a northern spillway that has 12 19-foot-tall, 20-
foot-wide radial tainter gates and a southern spillway with seven 19-
foot-high, 20-foot-wide radial tainter gates, and a valve house 
containing three butterfly valves and one Larner Johnson type valve at 
an elevation of 1,050.6 feet; (2) the 905-surface-acre Diablo Lake with 
a gross storage capacity of 88,880 acre-feet at normal maximum water 
surface elevation of 1,211 feet; (3) two bifurcated intake structures 
with four approximately 16.75- to 18.75-foot-wide, 153.71-foot-long 
openings and trashracks; (4) a 19.5-foot-diameter, 1,990-foot-long 
power tunnel, of which 1,800 feet is concrete-lined and the other 190 
feet is steel-lined; (5) two 15-foot-diameter penstocks and two 5-foot-
diameter penstocks each 290 feet long; (6) a surge tank; (7) a 
powerhouse containing four generating units with a total authorized 
installed capacity of 158.47 MW; (8) a switchyard; (9) a 230-kV, 5.8-
mile-long transmission line extending from Diablo Switchyard to the 
Gorge Switchyard; (10) three 230-kV, 87.6-mile-long transmission lines 
running from Diablo Switchyard to Bothell Substation; and (11) 
appurtenant facilities.
    The Gorge Development is located at RM 96.6 on the Skagit River and 
consists of: (1) a 300-foot-high, 670-foot-long combination concrete 
arch and gravity dam with a 94-foot-wide spillway that has two 50-foot-
high, 47-

[[Page 31262]]

foot-wide fixed wheel gates and a log chute; (2) the 235-surface-acre 
Gorge Lake with a gross storage capacity of 8,200 acre-feet at normal 
maximum water surface elevation of 881.5 feet; (3) a bifurcated intake 
structure with two 20-foot-wide, 88.9-foot-long openings and 
trashracks; (4) a 20.5-foot-diameter, 11,000-foot-long concrete-lined 
power tunnel; (5) three 10-foot-diameter penstocks and one 15-foot-
diameter penstock, each 1,600 feet long and each fitted with a 10-foot-
diameter butterfly biplane and relief valves; (6) a surge tank; (7) a 
powerhouse containing four generating units with a total authorized 
installed capacity of 189.3 MW; (8) a switchyard; (9) a 230-kV, 36.8-
mile-long transmission line extending from Gorge Switchyard to North 
Mountain Substation; and (10) appurtenant facilities.
    The three project developments are hydraulically coordinated to 
operate as a single project. Project operation under the existing 
license is designed to meet four objectives, which are prioritized as 
follows: (1) flood control, (2) salmon and steelhead protection flows 
downstream of Gorge Powerhouse, (3) recreation, and (4) power 
generation. To achieve these goals, City Light adheres to specific 
license requirements for Ross Lake levels and for stream flows and 
ramping rates downstream of Gorge Powerhouse.
    Under existing operations, Ross Lake is drawn down on a yearly 
basis during winter to capture flows from spring runoff and to provide 
for downstream flood control. The drawdown typically begins after Labor 
Day and continues until the lake reaches its lowest level in late March 
or early April. The current license requires City Light to draw down 
Ross Lake to a level that provides 60,000 acre-feet of storage for 
flood control by November 15 and 120,000 acre-feet by December 1 and to 
maintain this available storage through March 15. Ross Lake levels are 
also managed to meet recreational needs during the summer months. The 
current license requires City Light to fill Ross Lake as soon as 
possible after April 15, achieve full pool depth by July 31, and 
maintain full pool depth through Labor Day.
    The Diablo Development is operated to regulate flow between the 
Ross and Gorge Developments. Under normal operation, Diablo Lake 
typically fluctuates between 4 and 5 feet per day.
    The Ross Powerhouse and Diablo Powerhouse are typically operated 
continuously to pass flow downstream, although generation is 
occasionally increased or decreased for short periods to help meet 
load-following demand or other project purposes.
    The Gorge Development is operated primarily to provide a 
continuous, stable flow regime in the upper Skagit River for salmon and 
steelhead protection. City Light typically limits Gorge Lake 
fluctuations to about 3 to 5 feet and does not typically operate the 
powerhouse to meet load-following demand. The Gorge Development creates 
a 2.5-mile-long bypassed reach of the Skagit River between the dam and 
powerhouse. There are no minimum flow requirements in the existing 
license for the Gorge bypassed reach. Therefore, except during spill 
events at Gorge Dam, bypassed reach flow is limited to accretion flow, 
spill-gate seepage, tributary input, and precipitation runoff.
    l. In addition to publishing the full text of this notice in the 
Federal Register, the Commission provides all interested persons an 
opportunity to view and/or print the contents of this notice, as well 
as other documents in the proceeding (e.g., license application) via 
the internet through the Commission's Home Page (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 (P-553). 
For assistance, contact FERC at [email protected], (866) 208-
3676 (toll free), or (202) 502-8659 (TTY). At this time, the Commission 
has suspended access to the Commission's Public Reference Room. For 
assistance, contact FERC at [email protected] or call toll 
free, (886) 208-3676 or TTY (202) 502-8659.
    m. You may also register online at https://ferconline.ferc.gov/FERCOnline.aspx 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
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City Light files final study report for     March 2024.
 Study CR-04 Properties with Traditional
 Cultural Significance Study \1\.
Notice of Acceptance/Notice of Ready for    April 2024.
 Environmental Analysis.
Filing of recommendations, preliminary      June 2024.
 terms and conditions, and fishway
 prescriptions.
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\1\ City Light indicates in section 4.2.9.1 of the Final License
  Application Exhibit E that the study results for this Commission staff-
  approved study would be filed in the first quarter of 2024.

    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: May 9, 2023.
Kimberly D. Bose,
Secretary.
[FR Doc. 2023-10357 Filed 5-15-23; 8:45 am]
BILLING CODE 6717-01-P