LIHI Certificate # 43 --- Deer Island Hydropower Project (FERC No.11412) Deer Island Wastewater Treatment Plant, Boston Harbor Boston, Massachusetts.
Deer Island Hydropower Project (FERC No. 11412)
October 22, 2009 --- LIHI Governing Board Certifies Deer Island Hydropower Project at LIHI's Annual Meeting
Portland, Oregon (October 22, 2009) – At the Low Impact Hydropower Institute's (LIHI) Annual Meeting in Portland, Oregon, the LIHI Board unanimously voted to certify the Massachusetts Water Resource Authority's ( MWRA) Deer Island Hydroelectric Project The Project is located on the Deer Island Wastewater Treatment Plant , Deer Island, Boston Harbor Boston, Massachusetts.
The Deer Island Hydroelectric Project (FERC No. 11412) generates hydropower at its Deer Island Wastewater Treatment Facility. Once treated wastewater is disinfected, it is discharged into Effluent Channel 1. Flow is then split through two horizontal intake openings at base of Effluent Channel 1 and transmitted through separate rectangular concrete conduits below the disinfection basin to two corresponding hydro turbines. The two intake openings in Effluent Channel 1 are each approximately 20 feet by 18 feet. The intakes decrease to 11 feet by 11 feet at motorized roller intake gates located immediately upstream of the turbines. The average head available is approximately 29 feet. The hydropower facilities include two nominal 1,000 kw Kaplan units, each with flow capacity of approximately 500 cfs (320 mgd). The maximum flow (640 mgd) is approximately equivalent to the maximum flow through secondary treatment at DITP. Turbine runner blades and wicket gates are adjusted to meet changing power demands and changes in flow and head. After the turbines, the turbine effluent conduit joins the outfall chute which discharges into the outfall shaft which drops the effluent into the 9.5 mile outfall tunnel to Massachusetts Bay.
The Project is a conduit facility and received a conduit exemption from FERC. The hydroelectric facility was also part of a thorough environmental review by state and federal agencies as part of the Deer Island Water Treatment Plant. The Deer Island Treatment Plant discharges, including all discharges through the hydropower plant, received both an EPA NPDES permit and MA Division of Water Pollution Control Water Quality Certification for all discharges through hydropower plant.
The Deer Island Hydroelectric Project meets LIHI's eight environmentally rigorous Low Impact criteria addressing river flows, water quality, fish passage and protection, watershed health, endangered species protection, cultural resources, recreation use and access, and whether or not the dam itself has been recommended for removal. Deer Island Hydro Project has successfully completed LIHI's application process, which includes a public comment period, review by an independent technical consultant, consultations with state and federal natural resource agencies, and evaluation by the LIHI Governing Board, including leaders in the river conservation and renewable energy fields.
For more information about this LIHI certified facility or to see more about LIHI, take a tour of our web site www.lowimpacthydro.org or if you have questions call us in Portland, Maine 207-773-8190.
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Portland, Maine (August 6, 2009) – The Low Impact Hydropower Institute (LIHI) announced today that the Massachusetts Water Resource Authority ( MWRA) has submitted an application for certification of the Deer Island Hydroelectric Project ("Deer Island" or "Project") which is located on the Deer Island Wastewater Treatment Plant , Deer Island, Boston Harbor Boston, Massachusetts
Project Description
The Project generates hydropower at MWRA's Deer Island Wastewater Treatment Facility. Once treated wastewater is disinfected, it is discharged into Effluent Channel 1. Flow is then split through two horizontal intake openings at base of Effluent Channel 1 and transmitted through separate rectangular concrete conduits below the disinfection basin to two corresponding hydro turbines. The two intake openings in Effluent Channel 1 are each approximately 20 feet by 18 feet. The intakes decrease to 11 feet by 11 feet at motorized roller intake gates located immediately upstream of the turbines. The average head available is approximately 29 feet. The hydropower facilities include two nominal 1,000 kw Kaplan units, each with flow capacity of approximately 500 cfs (320 mgd). The maximum flow (640 mgd) is approximately equivalent to the maximum flow through secondary treatment at DITP. Turbine runner blades and wicket gates are adjusted to meet changing power demands and changes in flow and head. After the turbines, the turbine effluent conduit joins the outfall chute which discharges into the outfall shaft which drops the effluent into the 9.5 mile outfall tunnel to Massachusetts Bay.
The hydropower facilities' instrumentation and control system is designed to interface with the DI wastewater treatment facilities control system. The system allows fully automatic unattended operation. The treatment plant must operate continuously to prevent backups of the sewage collection system. Wastewater flow in excess of the hydro facility bypasses Effluent Channel 1 and is discharged through Effluent Channel 2 directly to the outfall tunnel. The building that houses the turbines, generators and all associated electrical switchgear equipment is situated directly over Effluent Conduit 1.
The building that houses the turbines, generators and all associated electrical switchgear equipment is situated directly over Effluent Conduit 1. An aerial view of the Deer Island Treatment plant is shown above; the structure housing the hydropower installation is indicated in the lower right hand corner of the figure and is within the configuration of the treatment plant. The building is bordered to the north by the outfall tunnel shaft, on the east by a seawall and MA Bay, on the south by disinfection basins, and on the west by secondary clarifiers. A profile and cross-sectional view of the hydropower facility are included in Figures 2 and 3. The facility is located some 200 feet from the shoreline and does not impact fisheries, wildlife, flood control, or navigation.
The Project is a conduit facility and received a conduit exemption from FERC. The hydroelectric facility was also part of a thorough environmental review by state and federal agencies as part of the Deer Island Water Treatment Plant. The Deer Island Treatment Plant discharges, including all discharges through the hydropower plant, received both an EPA NPDES permit and MA Division of Water Pollution Control Water Quality Certification for all discharges through hydropower plant.
PUBLIC COMMENT
We encourage public comments on this application. Specifically, we are interested in knowing whether you think the Deer Island Project meets our LIHI criteria. Review the program and criteria in greater detail and then review the Deer Island Project 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 (preferred) at info@lowimpacthydro.org with " Deer Island Project comments" in the subject line; by fax at (206) – 984-3086; or by mail addressed to LIHI, 34 Providence Street, Portland, ME, 04103. Comments must be received at the Institute on or before 5 pm Eastern time on October 6, 2009 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.