EDWARD MACDOWELL LAKE
NUBANUSIT BROOK - Merrimack River Basin - Peterborough, NH
DRAINAGE AREA: 44 sq.mi.
PERMANENT POOL: 102 Acre Recreation Pool
Elev: 912.0 ft NGVD
DAM
Type: Rolled Earth
Length: 1,100 Feet
Top Elev: 967.0 ft NGVD
FLOOD CONTROL STORAGE
Capacity: 12,650 Acre Feet
5.4 Inches of Runoff
Area at Crest: 840 Acres
CONTROL WORKS
Type: Conduit
Size: 7' x 7'
Length: 275 Feet
Invert Elev: 904.0 ft NGVD
Weir Elevation (top of logs, built Oct. 1985): 911.8 ft NGVD
Capacity (Full Pool): 1,600 cfs
Gates (Type): Power-driven Slide
Number: 3
Size: 3' x 7'
Channel Capacity: 650 cfs
SPILLWAY
Type: Chute Spillway/Ogee Weir
Length: 100 Feet
Elev: 946.0 ft NGVD
SPILLWAY DESIGN FLOOD
- Original Design Criteria:
- Rainfall Excess: 18.9 inches
- Initial Pool Level: Full
- Flood Control Outlet Gates: Inoperable
- Peak Inflow: 36,300 cfs
- Peak Outflow: 17,800 cfs
- Max. Pool: 960.8 ft-NGVD
- Freeboard: 6.2 ft
- Current HMR 51 & 52 Criteria:
- Rainfall Excess: 26.7 inches
- Initial Pool Level: Full
- Flood Control Outlet Gates: Operable
- Peak Inflow: 41,800 cfs
- Peak Outflow: 25,300 cfs
- Max. Pool: 964.1 ft-NGVD
- Freeboard: 2.9 ft
RECREATIONAL FACILITIES: 15 Picnic tables with grills, bathroom, water, parking, boat ramp, and group picnic shelter.
TOTAL COST: $2,034,300
PLACED IN OPERATION: April 1950