Morganza Spillway wells, and considerable swampland. Inhabitants know that the region is a natural floodplain, and the Corps of Engineers issues written notices annually to all interests reminding them of the possibility that it might open the spillway and flood the area. Any decision to open the spillway must be carefully planned to give ample warning and protect life and property. Part of that planning process includes the Corps' preparation of maps known as "inundation scenarios" so that interested parties can discuss how much water, if any, should be allowed through the spillway. During both moderate and severe floods of the Mississippi,
Pequannoc Spillway which lies on the Pompton River. The Pequannoc Spillway is an early 20th-century concrete spillway over 270 feet wide, equal in girth to the Great Falls of Paterson located along the Pompton River a quarter-mile south of the Pompton dam and associated guard bank in Pequannock Township's Aquatic Park. The dam is a run-of-the-river spillway, which traverses the width of the river and at normal water elevation allows water to spill over its face. The structure is 22 feet tall, though possesses only an 8-inch over 3 foot grade on the upstream side. An associated guard house sits near the