The Project consists of four hydro developments, Higley, Colton, Hannawa and Sugar Island, along the Raquette River in St. Lawrence County, New York.

The newly defined Middle Raquette River Project (MRRP or Project) is comprised of the Federal Energy Regulatory Commission’s (FERC) license 2320 that includes Erie Boulevard Hydro’s (EBH) Higley, Colton, Hannawa and Sugar Island hydro developments.

Project Name Middle Raquette
LIHI Certificate Number 14B
LIHI Effective and Expiration Dates July 9, 2014
July 9, 2019
Owner Brookfield Renewable Energy Group
State New York
Location Located along the Raquette River in St. Lawrence County, New York.
Installed Capacity 49.4 MW
Average Annual Generation 299.31 GWh
Facility Type Higley Development: Re-regulating
Colton, Hannawa, Sugar Island: Pulsing
FERC No. 2320

 

The Raquette River, with a total drainage basin of 1,269 square miles at its month, originates in the Adirondack highlands at Blue Mountain Lake, Raquette Lake and Long Lake, flows generally north-northwest for more than 120 miles, through Potsdam, New York and empties into the St. Lawrence River, near Massena, New York into the St. Lawrence River/Seaway at the St. Regis Indian Reservation in Franklin County.

The area experiences cold, snowy winters and short summers. Annual precipitation is about 40 inches. As the river flows north, it transitions from cold water habitat to a cool water aquatic fishery as the river reaches the lower gradients.

Most of the basin is sparsely populated, with much of the land forested and brush land. The Project is in a largely rural, forested area that is dependent on forestry, some agriculture, wood products, and tourism.  Historically, the river has been developed for water power for sawmills, paper mills, tanneries, and other industry.

In the Raquette River headwaters, the Carry Falls development, located at river mile (RM) 68 impounds 877 square miles (sq. mi.) of upstream drainage. This development’s seasonal storage pond is the largest on the Raquette River (RM 76 to 68) and is used to store and regulate the majority of this upstream flow to the downstream MRRP developments.  Flows below the MRRP’s most downstream project (Sugar Island) travel an additional ten miles before reaching the most upstream development in the LRRP (Norwood).

Four other FERC projects are located within this ten mile stretch of the Raquette River. They include the Potsdam Project (FERC-2869) (RM 35), owned by the Village of Potsdam, Sissonville Limited Partnership’s (SLP) Sissonville Project (FERC-9260) (RM 33) and EBH’s Hewittville (FERC-2499) (RM 32) and Unionville (FERC-2498) (RM 31) Projects, acquired in March of 2007. All of these projects have individual dams/spillways that receive inflow from the MRRP for power production. Project outflows are passed through each project and eventually become inflow for the LRRP.

The MRRP is located on the Raquette River from RM 47 to 38 in St. Lawrence County, NY about five miles below the URRP. This project consists of four developments, Higley, Colton, Hannawa, and Sugar Island, as shown in Table 1. Each development has a dam, reservoir, and powerhouse. In 2003, EBH redeveloped the Higley development and increased the installed capacity from 4.97 to 7.3 MW.

On December 13, 2011, EBH notified FERC of its initial powerhouse rehabilitation construction for its Hannawa Falls development. No changes were made to the powerhouse’s turbines or generators. The final construction report was submitted to FERC on October, 22, 2013.

Major Project Works

The Higley development has a total drainage area of 979 sq. mi. with an intervening drainage area of 37 sq. mi. between the Higley and the upstream URRP’s South Colton development. Higley operates as a re-regulating development to provide steadier flows for the downstream hydroelectric facilities. The other three developments of the MRRP operate in a pulsing mode. The Higley development consists of:

  • A 34-foot-high concrete gravity dam with;
    1. 3-foot-high wooden flashboards;
    2. A 209-foot-long concrete gravity ogee-crested spillway;
    3. Two flood gates,
    4. Eight steel forebay gates each measuring 12-feet high by 5-feet, 9-inches wide;
    5. A trashrack, and;
    6. Two 10-feet high by 8-foot wide waste gates;
  • A 160-foot long by 50-foot wide flume formed by concrete retaining walls on each side;
  • A retired in-place powerhouse measuring 64-feet a side by 38-feet high, containing three generating units with a total generating capacity of 4.972 MW;
  • A new intake structure with a 14 x 14-foot head gate, a 13-foot diameter, 225-foot long steel pipeline directly inflow to a new powerhouse;
  • A new redeveloped powerhouse measuring 90-feet long and 53-feet wide containing a single 7.3 MW generator;
  • Appurtenant electrical and mechanical facilities, and;
  • A reservoir with a 742-acre surface area and a 4,400-acre-foot usable storage capacity at normal maximum pool elevation 883.6 feet mean sea level (MSL).

The Colton development has a total drainage area of 981 sq. mi. with an intervening drainage area of 2 sq. mi. between the Colton and the upstream Higley development. The Colton development consists of:

  • a 27-foot high concrete gravity dam with;
    1. 2-foot-high flashboards;
    2. An 8-foot wide log flume;
    3. A trash gate, and;
    4. A 204.67-foot long ogee-crested spillway equipped with a single taintor gate measuring 10-feet high and 25-feet wide;
  • A reservoir with a 195-acre surface area and a 620-acre-foot usable storage capacity at normal maximum pool elevation of 837.0 feet MSL;
  • A concrete intake structure with a brick superstructure, which measures 50-feet wide by 30- feet long by 12-feet high overall, equipped with a motor driven, 16-foot high by 25.5-foot wide taintor gate;
  • A steel pipeline, 11,090-feet long with a diameter of 13.5-feet transitioning to a 2,100-feet long steel pipeline with a diameter of 12-feet;
  • An 80-foot-high Johnson differential surge tank;
  • Three penstocks of lengths 160-feet, 140-feet, and 125-feet, and diameters of 7.5-feet, 7.5-feet, and 9-feet respectively;
  • A brick and structural steel powerhouse measuring 165-feet long and 46-feet wide, containing three generating units with a total capacity of 30.1 MW.
  • Appurtenant electrical and mechanical facilities.

The Hannawa Falls development has a total drainage area of 993 sq. mi. with an intervening drainage area of 12 sq. mi. between the Hannawa Falls and the upstream Colton development. Hannawa Falls consists of:

  • A 38-foot high stone and concrete dam with:
    1. 5-foot-high wooden flashboards;
    2. A log chute;
    3. A motor operated taintor gate measuring 14-feet high by 28-feet wide;
    4. An ogee-crested spillway, and;
    5. A sluice gate;
  • A reservoir with a 204-acre surface area and a 690-acre-foot usable storage capacity at normal maximum pool elevation of 552.0 feet MSL;
  • A headworks structure with five sliding timber gates, all 18-feet high, with three 9.7-feet wide, one 9-feet wide, and one 8.8-feet wide;
  • A 2,700-foot long canal measuring 30-feet wide at the bottom, 120-feet wide at the top, with an average depth of 22-feet, equipped with trashracks that completely cover the canal entrance;
  • Two 10-foot diameter penstocks 190-feet long, and;
  • A sandstone and structural steel powerhouse measuring 66-feet wide by 248-feet long by 40-feet high containing two generating units with a total capacity of 7.2 MW, and;
  • Appurtenant electrical and mechanical facilities.

The Sugar Island development has a total drainage area of 994 sq. mi. with an intervening drainage area of 1 sq. mi. between the Sugar Island and Hannawa Falls developments. Sugar Island consists of:

  • A 37-foot high concrete gravity dam with;
    1. two taintor gates,  and;
    2. a 192-foot long spillway;
  • An earth saddle dike;
  • A concrete and brick intake structure with trashracks and a steel head gate measuring 14-feet wide by 16-feet high;
  • A 4,700-foot long steel pipeline;
  • A 71-foot high surge tank;
  • Two 8-foot-diameter penstocks;
  • A brick and structural steel powerhouse measuring 35-feet wide by 67-feet long by 30-feet high containing two generating units with a total capacity of 4.800 MW
  • A reservoir with a 29-acre surface area and a 55-acre-foot usable storage capacity at normal maximum pool elevation of 470.0 feet MSL;
  • Appurtenant electrical and mechanical facilities.

Project Operations

The MRRP operation is coordinated with EBH’s other LIHI projects on the Raquette River, the URRP and the LRRP. As described in the Raquette River Project Offer of Settlement (RRPSO), submitted to FERC on April 22, 1998[1] and the 2002 FERC license[2], the MRRP’s most upstream development, Higley, operates as a re-regulating development to provide steadier flows for the downstream hydroelectric facilities within the MRRP and LRRP.

Each of the MRRP developments below Higley are allowed to operate in a pulsing mode that limits the normal reservoir fluctuation at Colton and Hannawa to no more than 0.4 feet, and at Sugar Island to no more than 1.0 foot.

Each development generates when total inflow is available to pass the minimum bypass flow plus run one turbine at its minimum turbine limit. Once a development’s net inflow (inflow available after passing minimum flow) exceeds the powerhouse’s hydraulic capacity, the powerhouse is run at full hydraulic capacity and all excess water is passed over the spillway or top of flashboards.

The MRRP developments have an overall installed capacity of 49.4 MW and produce an average annual energy (AAE) of 299.31 GWh (Plant factor of 69.1%).

[1] The RRPSO  – http://elibrary.ferc.gov/idmws/search/intermediate.asp?link_info=yes&doclist=1845587

[2] Copy of February 13, 2002 FERC License – http://elibrary.ferc.gov/idmws/common/OpenNat.asp?fileID=13707261

Certification History

May 15, 2015: The Middle Raquette River Hydroelectric Project has been certified for a third term of low impact certification, effective July 9, 2014 and expiring July 9, 2019, with the following conditions:

  1. Facility owner shall develop a draft Deviation Reduction Plan (DRP) and submit it to LIHI no later than three months after LIHI certification of MRRP. The DRP define proactive operational control approaches for dam releases and pond level maintenance that will reduce the likelihood of operational deviations occurring in the future.  The DRP needs to address the specific problems and potential recommendations identified in the reviewer’s report. Options to be considered should include audible alarms in control centers and programmable logic controllers. The DRP shall describe options considered, those selected, and a schedule for implementation.  LIHI staff will review and comment on the draft plan and be available to assist in the development of the DRP, if requested. The final DRP needs to be completed and agreed to by both EBH and LIHI no later the six months after LIHI certification.
  1. Facility owner shall provide annual reports to LIHI documenting operational deviations from instream flow or pond levels that occurred throughout each year of certification. The report shall describe all deviations that have occurred, regardless of whether the deviations were planned or unintentional or whether they are eventually deemed as not violating the license by FERC. The report is due at the same time as the annual compliance statement and payment of the annual certification fee.

In rendering this Certification, the Institute’s Executive Director used authority delegated by the LIHI Governing Board and a full review of the Application Reviewer’s report (available in the Files section below) and all public comments and additional materials provided by the Applicant.

June 4, 2014: The Low Impact Hydropower Institute received a comment letter from the U.S. Fish and Wildlife Service regarding the recertification of the Raquette River Project. The letter is available to read in full in the “Files” section below.

May 23, 2014: The Low Impact Hydropower Institute received a comment letter from John Omohundro regarding the recertification of the Raquette River Project. The letter is available to read in full in the “Files” section below.

May 12, 2014: The Low Impact Hydropower Institute received an application for a third term of certification of the Raquette River Project. The current certificate term is set to expire on July 9, 2014, but to allow time for public comment and internal review, the term has been extended to August 30, 2014.

April 15, 2010: The Raquette River Project has been certified as low impact for a second five year term, effective July 9, 2009 and expiring July 9, 2014.

October 27, 2004: The Raquette River Project has been certified as low impact for a five year term, effective July 9, 2004 and expiring July 9, 2009.

Files: