Milton Seaman Dam Spillway Rehabilitation Project

Milton Seaman Dam Reservoir is owned and operated by the City of Greeley, Colorado and is located on the North Fork Cache la Poudre river about 15 miles northwest of Fort Collins, Colorado. The dam and spillway were constructed in 1948. The original 1948 design included the embankment, outlet works tunnel, gate house, parapet wall, and an unlined spillway cut through a natural saddle. In 1965, the dam crest was raised, the spillway was lined with concrete and an ogee weir was added to increase the reservoir elevation by 5 feet.
The spillway chute has deteriorated since the 1965 enlargement as shown in Figure 1. Water has been seeping steadily through weep holes and construction joints since the enlargement. Seepage has also surfaced through the full length of the discharge channel. The discharge channel has eroded apparently from spillway discharge and freeze-thaw action.