Putts Bridge Dam

The Putts Bridge Project (the “Project”) is exempt from licensing by the Federal Energy Regulatory Commission (“FERC”) as Project No. 10677.  The Project is owned by Essential Power, LLC (“Essential Power”). [1]  The project is located in the Towns of Wilbraham and Ludlow and City of Springfield in Hampden County, Massachusetts, at approximate river mile 9.2 on the Chicopee River.  The Project dam crosses the town line between Springfield and Ludlow; the powerhouse is located in Ludlow.  The impoundment extends in a northeasterly direction, bordering Springfield and Ludlow.  The Project was originally constructed in 1918 by the Ludlow Manufacturing Company.  In 1988, the Federal Energy Regulatory Commission determined that the Chicopee River was a navigable waterway under its jurisdiction and ordered WMECO to prepare an application for Exemption from Licensing.

Project Name Putts Bridge
LIHI Certificate Number 102
LIHI Effective and Expiration Dates December 20, 2012
December 20, 2017
Owner Essential Power LLC
State Massachusetts
Location Located at approximate river mile 9.2 on the Chicopee River in the Towns of Wilbraham and Ludlow and City of Springfield in Hampden County, Massachusetts.
Installed Capacity 3,900 KW
Average Annual Generation 15,500 MWh
Facility Type Limited pond-and-release
FERC No. 10677

The existing major project works include a dam with a crest elevation of 203.6 feet (NGVD), an impoundment, a concrete headgate structure, two conduits, forebay, trashrack, intake structure, a powerhouse with two generating units, a tailrace channel (normal tailrace elevations 160.9 feet) and appurtenant facilities.

The dam, built in 1918, crosses the Chicopee River in a roughly north-to-south direction, and is a concrete gravity structure approximately 223-foot long by 22-foot high.  The northern abutment of the dam is contiguous with the abutment for the Ludlow Avenue Bridge.  Adjacent to this abutment are a skimming gate with invert at El. 199.7 feet and a deep sluice gate with invert at El. 183.9 feet. The deck elevation at the two gates is El. 212.9 feet.  A 23-foot non-overflow section extends from the gate area to the 200-foot long ogee spillway which extends across the river to the south abutment, El. 212.9 feet.  A concrete retaining wall extends from the south abutment at El. 212.9 feet for approximately 133 feet.

At normal pond elevation the Putts Bridge Project impoundment extends approximately 3.3 miles upstream of the dam.  At normal pond condition, the maximum surface area is approximately 65 acres at El. 205.3’.  While the maximum useable storage of the reservoir is 323 acre-feet, the used storage capacity is just 65 acre-feet.  While the permitted daily drawdown is 1 foot during the spring and 2 foot for the balance of the year (except during energy audits and system emergencies when this limit may be exceeded), the actual year-round drawdown is 1 foot.

The concrete headgate structure is adjacent to the northeast abutment of the dam, and has a deck elevation of 212.9 feet.  Six motorized headgates, each approximately 12 feet wide by 13.3 feet high direct the flow to the underground concrete conduits that lead to the powerhouse forebay.  A double-barreled, underground concrete conduit extends 647 feet from the impoundment to the forebay.  Each barrel of the conduit is 16.5 feet high by 12.5 feet wide.

The forebay is a reinforced concrete structure measuring 40 feet wide by 104 feet long.  The forebay is 41.5 feet high, with a top elevation of 210.3 feet.  There is a 2.5-foot diameter spigot type drain gate at the base of the forebay, and an 18-foot wide skimming gate on the north forebay.

The trashrack is situated along the western forebay wall, extending from the floor of the forebay (El. 169.4 feet to El. 208.1 feet).  There is a mechanical trash rake mounted on rails along the entire width of the trashrack.  Wooden headgates, measuring 14.3 feet square, isolate the forebay from the generating units.

The Putts Bridge Project powerhouse has a concrete substructure with a brick superstructure.  It measures 45 feet wide by 154 feet long.  The structure houses the two operating units, No.2 and No.3, and one retired, No. 4.  Unit No.1 was never installed although the turbine pit is there.  Unit No.5 is a retired waterwheel exciter.  The normal tailrace elevation is 160.9 feet.  The tailrace canal runs 355 feet from the powerhouse in a westerly direction to where the flow re-enters the Chicopee River.

The powerhouse’s 11.5 KV generators are connected to 11.5 KV circuit breaker to a 4.5 MVA autotransformer located at WMECO’s North Street substation.  At the substation, the autotransformer steps the voltage up from 11.5 KV to 13.8 KV for interconnection to WMECO’s 13.8 KV distribution system.

The Putts Bridge project is situated upstream of three other hydroelectric facilities located on the Chicopee River[2] and downstream of two other dams on the Chicopee River as well as other dams on the Ware, Swift and Quaboag Rivers.[3]  Two of the three downstream hydroelectric facilities are owned and operated by Essential Power – Dwight Station Project (P-10675) and Indian Orchard Project (P-10678).  The Red Bridge Project (P-10676) is owned and operated by Essential Power and is located upstream of the Project.  The Project drains an area of 686 square miles.

Immediately upstream of the Putts Bridge Project is Collins Dam Project (P-6544) and immediately upstream of Dwight Station Project is Chicopee Falls Dam (P-6522).   The Project and the other Essential Power dams on the Chicopee River have little to no control over their inflows.  Collins Hydro and Chicopee Falls dams[4] are owned and operated by unrelated entities as are all of the hydroelectric projects on the upstream tributaries of the Chicopee River.

The Putts Bridge project is operated in a limited pond-and-release mode, utilizing the useable storage capacity (65 acre-feet) afforded by a 1.0 foot drawdown during the second quarter and 2.0 foot drawdown during the balance of the year.[5]  The station is operated semi-automatically by float controls.  The operating mode of the Putts Bridge project does not change during dry, mean or high water years.  As flows vary at the Project, the number of turbines operating and the duration of operation changes, increasing and decreasing the amount of generation realized.

[1] Until the late 1990s, the Project was owned by Western Massachusetts Electric Company when the Project was sold to Consolidated Edison Energy, Inc. (“CEEI”), an affiliate of Consolidated Edison Company of New York, Inc.  In 2008, the Project was sold to its current owner, Essential Power.

[2] The order of the hydroelectric dams, starting with the lowest dam, on the Chicopee River is Dwight Station Project (P-10675) river mile 1.2, Chicopee Falls Project (P-6522) river mile 3.0, Indian Orchard Project (P-10678) river mile 7.8, Putts Bridge Project (P-10677) river mile 9.2, Collins Hydro Project (P-6544) river mile 12.6 and Red Bridge Project (P-10676) river mile 15.2.

[3] For example, the first dam on the Ware River is Thorndike Dam river mile 20.5 while the first dam on the Swift River is the Upper Bondsville Dam river mile 20.1. (No dams were identified on the Quaboag River).

[4] The owners/operators of the Collins Hydro and Chicopee Falls projects are also unrelated to each other.

[5] Although the Project has a two-foot drawdown for the non-spring periods of the year, the Project operates year-round with a one-foot drawdown.

Putts Bridge Powerhouse

Putts Bridge Powerhouse 2

Certification History

March 12, 2013: The Putts Bridge Hydroelectric Project has been certified as low impact for a five year term, effective December 20, 2012 and expiring December 20, 2017, with the following conditions:

  1. As the final confirmation that the recently submitted Minimum Flow and Impoundment Fluctuation Monitoring Plan sufficiently addresses compliance with the various flow requirements is contingent upon review and approval of six months of flow data by the USFWS, Essential Power shall provide LIHI a letter documenting that such records have been provided within nine months of Project certification.
  1. Essential Power shall certify to LIHI that the 24-hour period of empirical data to compare with the calculated flows for USFWS’s evaluation of the Flow Monitoring Plan has been provided. Essential Power shall also provide LIHI, documentation of the USFWS review/approval or concerns found with this data comparison within nine months of Project Certification.
  1. Should the review process in Condition #2 find that modifications are needed to the Flow Monitoring Plan, Essential Power shall forward a copy of the modifications, along with resource agency approval of these modifications, within one month of the Plan submission to FERC. Essential Power shall also provide LIHI a copy of FERC’s final Plan approval within one month of receipt of this approval.

February 18, 2013: Public comment period on application has closed.

December 20, 2012: Essential Power LLC has submitted an application for the certification of the Putts Bridge project. Application has been posted and the public comment period has opened.

Putts Bridge Spillway (1)

 

Putts Bridge Tailrace

 


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