Genesee Reservoir No. 2

Reservoir

Genesee's Water Storage Reservoir:

Genesee Water & Sanitation District built a dam and reservoir in 2008 that is on a small gulch tributary to Bear Creek half way between Idledale and Kittredge near mile marker 12 on State Highway 74. It can only be viewed from a small section of eastbound 74.

Dam Statistics: Building a safe and secure dam was the number one concern of the District. Minimizing environmental impacts and preserving the natural beauty of the canyon followed by safety were top priorities as well. The following summarizes key elements of the project:

Closest Downstream Town

Idledale

Distance to Downstream Town

2.2 Miles

River or Stream

Unnamed Tributary of Cold Springs Gulch

Dam Type

Roller Compacted Concrete (RCC) Gravity Dam

Dam Height

111 Feet (RCC Structural Height)

Hydraulic Height

92 Feet (Bottom of Reservoir to Dam Crest)

RCC Dam Crest Length

375 Feet

RCC Dam Crest Width

16 Feet

Reservoir Surface Area

2.8 Acres at the Service Spillway Crest

Normal Storage Capacity

101.2 Acre-Feet at the Service Spillway Crest

Maximum Storage Capacity

127.4 Acre-Feet at the Top of the Parapet Wall

Drainage Basin Area

0.58 Square Miles

Outlet Discharge Capacity (At 6,788.25  Feet Elevation

22 Cubic-Feet/Second (cfs)

Service Spillway Capacity (At 6,793 Feet Elevation

562 Cubic-Feet/Second (cfs) at the Emergency Spillway Crest

Emergency Spillway Capacity

4,208 Cubic-Feet/Second (cfs) at the Top of the Parapet Wall

Combined Emergency and Service Spillway Capacity

5,027 Cubic-Feet/Second (cfs) at the Top of the Parapet Wall

Emergency Spillway Crest

6,793 Feet Elevation

Emergency Spillway Length

200 Feet

Top of Parapet Wall

6,797 Feet Elevation

Parapet Wall Length

175 Feet

FACTS:

  • 58,300 cubic-yards of soil will be used to construct the downstream berm against the downstream face of the RCC dam.
  • 2,900 cubic-yards of conventional concrete were placed for the upstream dam face, the spillway tower, and the spillway outlet structure.
  • 34,300 cubic-yards of roller compacted concrete were used to construct the dam's gravity section.
  • 33,100 cubic-yards of native rock and gravel were used in the construction of the dam. This negated the need to haul in large volumes of material minimizing environmental impacts and traffic disruptions.
  • A grout curtain extends a minimum of 50 feet below the dam's foundation to minimize foundation seepage.