Crystal Lake Dam is an earth-filled embankment dam. It is approximately 1200 feet long, 10-feet high containing an approximate 110' long concrete core, approximately centered on a 41' wide concrete trough spillway.
The spillway is approximately 31' feet long with 3' concrete sidewalls. The spillway descends approximately 3' onto a concrete drop apron, trapezoidal in shape, after which the discharge flow spills into an outflow channel approximately 100' from its confluence with the Ramapo River.
A 36-inch diameter outlet pipe and slide gate on the eastern side of the spillway provide low-level outlet control.
Approximately 900' north of the spillway is a 24-inch diameter secondary low-level outlet pipe with control gate. The reinforced concrete pipe penetrates the embankment and exits through a concrete headwall on the easterly bank of the Ramapo River. The 24-inch low-level outlet structure provides an alternate means to lower the lake for maintenance.
NEW JERSEY DAM SAFETY LAWS: SAFE DAMS ACT (N.J.S.A. 58:4)