NORTH HARTLAND DAM

Project has Non-Federal Hydropower (see below)

 

OTTAUQUECHEE RIVER - Connecticut River Basin - No. Hartland, VT

 

DRAINAGE AREA: 220 sq.mi.

PERMANENT POOL:  215 Acre Recreation Pool, Stage = 35 Ft

 

DAM

Type: Rolled earth fill

Length: 1,640 Feet

Top Elev = 572.0 Ft NGVD (182 Ft)

 

FLOOD CONTROL STORAGE

Capacity: 71,000 Acre Feet

6.1 Inches of Runoff

Area at Crest: 1,100 Acres

 

CONTROL WORKS

Type: Circular Conduit

Size: 14'-4" diameter (steel lined as a 12-ft dia. for hydropower)

Steel Penstock Length: approx. 1200 ft (inside Dam to bypass Gate)

Upstream Invert Elev = 390.0 Ft NGVD

Bypass Gate: 1 @ 8'-4"W x 12'H

Bypass Invert Elev = 380.90 Ft-NGVD

Capacity (Full Pool): 7,000 cfs

Bifurcated Penstock: 12-ft dia. For 175-ft; then transition to 9-ft dia. into Powerhouse

Dam Sluice Gates:

Gates (Type): Hydraulic Slide

Number: 3

Size: 5'-8" x 10'

Channel Capacity = 6,000 cfs

 

SPILLWAY

Type: L-shaped Side-Channel

Length: 465 Feet

Elev = 546.5 Ft NGVD (156.5 Ft)

 

SPILLWAY DESIGN FLOOD

 

  • Original Design Criteria:

Rainfall Excess = 17.2 inches

Initial Pool Level = Full

      Flood Control Outlet Gates = Operable

      Peak Inflow = 199,000 cfs

      Peak Outflow = 171,000 cfs

      Max. Pool = 566.8 ft-NGVD

      Freeboard = 5.2 ft

   

  • Current HMR 51 & 52 Criteria:

      Rainfall Excess = 20.3 inches

      Initial Pool Level = Full

      Flood Control Outlet Gates = Operable

      Peak Inflow = 217,600 cfs

      Peak Outflow = 180,700 cfs

     Max. Pool = 568.1 ft-NGVD

      Freeboard = 3.9 ft

   

HYDROPOWER

Non-Federal owned by Essex Hydro Assoc.

Active Since Oct. 2005

Peaking Operation

Installed Cap = 4.0 MW

Normal Power Pool: 35 ft

Head Operating Range: 1-3 ft Seasonally

Turbine Op Range: 200-810 cfs

 

RECREATIONAL FACILITIES: 23 Picnic tables, water, parking areas, bathroom, boat ramp, and 2 group picnic shelters. Quechee Gorge state leased campground, with 30 campsites and fireplaces.

 

TOTAL COST: $7,130,000

 

PLACED IN OPERATION: January 1961