Hydraulic Transient Study of Passaic River Flood Protection Tunnel

The purpose of this study is to evaluate the hydraulic transient status in the proposed Passaic River Flood Protection Tunnel. The tunnel system is designed to convey flood waters from the upstream areas of Passaic River directly into Newark Bay. The tunnel consists of two upstream inlets, the Pompton Inlet and the Spur Inlet, and a 42 ft diameter main tunnel. The main tunnel length is about 20.1 miles (from the Pompton inlet to the downstream end). The distance between the Spur inlet and the main tunnel is about 1.2 miles. The tunnel system will be excavated from 150 to more than 400 ft under ground. From the hydraulic transient point of view, there are the following possible safety concerns in this tunnel system, which need to be evaluated using hydraulic transient computer. simulation program. (1) Surge phenomena induced during the initial filling stage. (2) Water hammer phenomena due to a sudden pressure change. (3) The effects of the surge and water hammer on the inlets, workshafts, and downstream outlet.