COLEBROOK RIVER DAM

Project has Non-Federal Hydropower (see below)

WEST BRANCH FARMINGTON RIVER - Connecticut River Basin - Colebrook, CT

DRAINAGE AREA = 118 sq.mi.
PERMANENT POOL = 708.0 Ft NGVD (133 Ft), 750 Acre Multi-Purpose

DAM

Type = Rolled earth fill and rock fill
Length = 1,300 Feet
Top Elev = 790.0 Ft NGVD (215 Ft)

FLOOD CONTROL STORAGE

Capacity = 50,200 Acre Feet, 8.0 Inches of Runoff
Area at Crest = 1,185 Acres

CONTROL WORKS

Type = Tunnel in rock
Size = 10' diameter
Length = 774 Feet
Invert Elev = 575.0 Ft NGVD
Capacity at Full Pool = 4,500 cfs
Gate (Type) = Hydraulic Sluice
Number = 3
Size = 4' x 8'
Channel Capacity = 3,000 cfs

SPILLWAY

Type = Chute Spillway
Length = 205 Feet
Elev = 761.0 Ft-NGVD (186 Ft)

SPILLWAY DESIGN FLOOD

Original Design Criteria

Rainfall Excess = 21.2 inches
Initial Pool Level = 6" of F.C.
Flood Control Outlet Gates = Operable
Peak Inflow = 165,000 cfs
Peak Outflow = 96,000 cfs
Max. Pool = 780.0 ft-NGVD
Freeboard = 5.0 ft

Current HMR 51 & 52 Criteria

Rainfall Excess = 23.99 inches
Initial Pool Level = 6" of F.C.
Flood Control Outlet Gates = Operable
Peak Inflow = 195,600 cfs
Peak Outflow = 126,200 cfs
Max. Pool = 788.3 ft-NGVD
Freeboard = 2.2 ft

HYDROPWER

Non-Federal owned by Metropolitan District of Hartford, CT
Active since 1989
Installed Cap = 3.0 MW
2 banks of turbines with 3 turbines/bank
Each Bank operating Head Range: 25-100 ft
Each Bank operating Flow Range: 75-350 cfs
Total Turbine Flow Range: 75-700 cfs

WATER SUPPLY & CONSERVATION

Replacement Pool	643.7 ft-NGVD	(total 11,800 ac-ft, 3.88 BG)
Water Supply Pool	701.2 ft-NGVD	(total 42,500 ac-ft, 10 BG)
Conservation (Fall Fisheries) Pool	708.0 ft-NGVD	(net 5,000 ac-ft, 1.63 BG)
Spring Fisheries Pool	714.5 ft-NGVD	(net 5,000 ac-ft, 1.63 BG)

RECREATIONAL FACILITIES = Multi-level boat ramp, 2 parking areas (including 76 car/boat/trailer spaces), portable sanitary facilities.

TOTAL COST = $14,115,000

PLACED IN OPERATION = June 1969

GOODWIN DAM (West Branch Reservoir)

Storage Capacity = 8,900 acre-feet (1.4 inches)
Top of Dam = 656.0 ft NGVD (135 ft)
Spillway
  Elev = 641.0 ft NGVD
  Length = 900 ft
  Pool Surface Area = 200 acres
Completed in 1960