LIHI Certificate #169 - Cataract Project, Maine

The Cataract Project (FERC No. 2528) consists of four developments including one hydroelectric development located in Saco and Biddeford and three in the towns of Dayton and Buxton, Maine. The four developments are located between river miles 6.0 and 6.3 on the Saco River and, listed from upstream to downstream are: Bradbury, Spring Island, West Channel and East Channel. The portion of the Saco River downstream of the West and East Channel Dams is tidally influenced.

The dams at Spring Island, Bradbury, and West Channel pre-date the present East Channel power development which was developed in 1938. The developments were originally constructed around the turn of the century to meet the hydromechanical and hydroelectric demands of the Saco River. The Project is owned and licensed by Brookfield White Pine Hydro, LLC, and the four dams are operated to supply a single powerhouse with a single Kaplan turbine/generator with authorized installed capacity of 6.65 MW and average annual generation of 30,868 MWh.

The project is operated in a run-of-river mode with minor fluctuations in headpond elevation and minimum flows of 851 cfs downstream of the West Channel Dam and East Channel Dam. Operation of the project is managed in conjunction with the water flow and storage of upstream and projects in accordance with the 1997 Saco River Instream Flow Agreement.

Bradbury Development:

Bradbury Dam consists of a concrete gravity overflow structure extending from the south shore, and one gate section. The spillway section is 141 feet long, has a fixed crest elevation of 47.7 feet with 20-inch-high pin-supported flashboards and abuts the gate section. The gate section contains a Tainter gate measuring 20.25 feet wide by 13.5 feet high with a sill elevation of 36.2 feet. North of the gate section is a lock system for upstream fish passage. The lock system is approximately 41 feet long by 10 feet wide and contains an attraction flow flume, fish crowder, lock chamber, control gates, and exit way.

Spring Island Development:

Springs Dam consists of a natural like fishway approximately 100 feet wide by 230 feet long beginning at the East shore, an overflow section and two gate house sections. The overflow section is a concrete gravity structure with a fixed crest at elevation of 47.7 feet. It is topped with 18-inch pin-supported flashboards, extends 117.5 feet from the natural like fishway to the first gate section. The gate house has four gate openings with sills at an elevation of 39.2 feet. There are three Taintor gates, each 16 feet wide by 11 feet high. The most easterly of the openings is closed by timber stop logs and a slide gate operated manually with a chain hoist.

West of the gate section is a lock system for upstream fish passage. The lock system is approximately 41 feet long by 10 feet wide and contains an attraction flow flume, fish crowder, lock chamber, control gates, and exit way.

Spring Island and Bradbury Impoundment:

The impoundment created by Bradbury and Springs dams has a normal full pond elevation of 49.2 feet, an area of about 359 acres, and extends upstream approximately 9.3 miles to the Skelton Project (FERC No. 2527). The useable storage capacity under the existing two-foot pond cycling is 31 million cubic feet.

West and East Channel Impoundment:

The pond created by East and West Channel dams has a normal full pond elevation of 44.0 feet, covers an area of about 13.7 acres and extends upstream approximately 0.3 miles to the Springs and Bradbury dams.

West Channel Development:

The West Channel Dam consists of two overflow sections, a downstream fish passage weir, an upstream denil fish ladder, and a gate section. The first overflow section is a gravity structure of stone masonry and concrete construction with a concrete cap. It has a crest at elevation 40.5 feet. This section extends from the west bank 193 feet to an angle point and 44.5 feet from the angle point to the former fishway. This overflow section is equipped with a four- foot-high inflatable rubber bladder. The second overflow section extends from the gate section to the denil fish ladder and downstream fish sluice. This section is a concrete gravity structure, 24 feet long and has a crest at elevation 40.5 feet with four-foot-high pin-supported flashboards.

Upstream passage at the West Channel dam is by means of a denil fish ladder. There are also sorting facilities at this site. The denil ladder is four feet wide and approximately 550 feet long. The vertical rise is approximately 44 feet on a 1 vertical to 8 horizontal slope. The Exhibit F drawings show the facility details. The outdated notched weir and orifice fishway in the West Channel has been abandoned since 1991. Downstream passage consists of a gated flume.

East Channel Development:

The East Channel dam consists of an overflow section, a gate section, and an intake section. The overflow section is an 88-foot 8-inch-long concrete gravity structure with a fixed crest at elevation of 39.5 feet, topped by five-foot-high pneumatic crest gates. The crest gates are operated from a 10-foot-high by 12-foot-wide by 16-foot-long control building located above the powerhouse intake. The East Channel gate section contains a vertical lift Broome gate, 20 feet wide by 15 feet high. The sill of the gate is at an elevation of 29 feet. The powerhouse intake section is 49 feet 3 inches wide and is equipped with racks and two intake openings.

The powerhouse is located on Factory Island on the East Channel. The substructure, approximately 37 feet by 53 feet, houses a 9,000 HP Kaplan, S. Morgan Smith water wheel. The draft tube angles about 20 degrees to the intake and extends 30 feet downriver from the substructure where it discharges into tidewater. Two gates, each 15 feet wide by 12 feet 10 inches high are installed at the downstream end of the draft tube. The powerhouse superstructure is of structural steel and brick construction and houses a 6,650-kW generator (9,500 kVA at 0.7 P.F.) and associated equipment. A 60-ton capacity bridge crane is installed to service the unit.

Upstream passage is provided at the East Channel dam with a fish lift. The facilities include sorting and trap/truck provisions. The fish lift travels vertically approximately 44 feet from the tidal pool to the headpond. A 337-foot-long, 8-foot-wide flume extends upstream to the sorting facilities and the headpond. The sorting facilities include trap and trucking measures. Downstream passage consists of a gated flume.

Project Name Cataract
Owner Brookfield White Pine Hydro, LLC
State Maine
Location Between River Mile 6.0 and 6.3 on the Saco River
Installed Capacity 6.65 MW
Average Annual Generation 30,868 MWh
Facility Type Run of river
FERC No. 2528, issued June 29, 1989, expires November 30, 2029

Certification History

July 30, 2020: The decision to certify the Cataract Project became final after the close of the appeals period on July 22, 2020 with no appeals filed. The Certification term is from April 3, 2020 – April 2, 2025.

June 22, 2020: The Low Impact Hydropower Institute has preliminarily approved Low Impact Certification for the Cataract Hydroelectric Project, pending LIHI #169 located on the Saco River in the towns of Saco and Biddeford, Maine.  The certification includes one condition:

Condition 1: The facility Owner shall provide documentation to LIHI that the West Channel diversion wall and the flume extension at the entrance to East Channel fishway are completed and operational no later than May 1, 2021; or if not completed by that time, the Owner shall provide a report on the status of the project including resource agency consultation and a timeline for completion of the project.
This decision is preliminary pending the 30-day appeal window. Only those who commented on the initial application during the 60-day comment period are eligible to file an appeal. Such appeal needs to include an explanation as to how the Project does not meet the LIHI criteria. Appeal requests can be submitted by email to comments@lowimpacthydro.org with “Cataract Hydroelectric Project” in the subject line, or by mail addressed to the Low Impact Hydropower Institute, 329 Massachusetts Ave, Suite 6, Lexington, MA 02420. All requests will be posted to the website.  The applicant will have an opportunity to respond and any response will also be posted. Requests must be received by 5 pm Eastern time on July 22, 2020.  The full application and reviewers report are available below.

If no appeal requests are received and the decision becomes final, the Certification term for the Project will be from April 3, 2020 to April 2, 2025.

April 7, 2020: The Low Impact Hydropower Institute has received a complete application for Low Impact Certification of the Cataract Hydroelectric Project.   The Project’s application materials can be found below.

LIHI is seeking public comment on this application. Comments that are directly tied to specific LIHI criteria (flows, water quality, fish passage, etc.) will be most helpful, but all comments will be considered.  Comments may be submitted to the Institute by e-mail at comments@lowimpacthydro.org with “Cataract Project Comments” in the subject line, or by mail addressed to the Low Impact Hydropower Institute, 329 Massachusetts Avenue, Suite 6, Lexington, MA 02420.  Comments must be received on or before 5 pm Eastern time on June 6, 2020 to be considered.  All comments will be posted to the web site and the applicant will have an opportunity to respond.  Any response will also be posted.