NORTHFIELD BROOK DAM (UNSTAFFED)

NORTHFIELD BROOK - Naugatuck River Watershed - Thomaston, CT

DRAINAGE AREA: 5.7 sq.mi.

PERMANENT POOL: 22.5 ft, 8 Acres Recreation Pool

DAM
Type: Rolled Earth Fill
Length: 810 Feet
Top Elev = 591.0 ft NGVD (110.5 ft)

FLOOD CONTROL STORAGE
Capacity: 2,350 Acre Feet
7.7 Inches of Runoff
Area at Crest: 67 Acres

CONTROL WORKS
Type: Circular concrete conduit
Size: 3' diameter
Length: 544 Feet
Invert Elevation (weir gate): 480.5 ft NGVD
Weir Elevation (top of logs): 503.0 ft NGVD
Capacity (Full Pool): 160 cfs
Gate (Type): Preset gate
Number: 2
Size: 3' x 3'(fixed at 1.1 ft opening)
and 2' x 3'(weir gate)
Channel Capacity = 200 cfs

SPILLWAY
Type: Chute Spillway/Ogee Weir
Length: 72 Feet
Elev = 576.0 ft NGVD (95.5 ft)

SPILLWAY DESIGN FLOOD

Original Design Criteria:
- Rainfall Excess: 23.2 inches
- Initial Pool Level: Full
- Flood Control Outlet Gates: Operable
- Peak Inflow: 9,000 cfs
- Peak Outflow: 8,800 cfs
- Max. Pool: 586.1 ft-NGVD
- Freeboard: 4.9 ft
Current HMR 51 & 52 Criteria:
- Rainfall Excess: 32.4 inches
- Initial Pool Level: Full
- Flood Control Outlet Gates: Operable
- Peak Inflow: 15,350 cfs
- Peak Outflow: 14,500 cfs
- Max. Pool: 589.8 ft-NGVD
- Freeboard: 1.2 ft

RECREATIONAL FACILITIES: 90 Picnic tables, beach, parking areas, restrooms, two group picnic shelters, and hiking trail.

TOTAL COST: $2,810,000

PLACED IN OPERATION: October 1965