Impact of flood-diversion tunnel on Newark Bay and adjacent waters

A diversion tunnel has been proposed to alleviate flooding in the upper portion of the Passaic River basin. The tunnel will divert flow from the headwaters of the Passaic to the upper end of Newark Bay. The present study provided information required to evaluate the effect of the tunnel on finfish and shellfish in the vicinity of the outlet. Impacts were examined through the CH3D hydrodynamic model and the CE-QUAL-ICM water-quality model. Quantities computed included tides, currents, salinity, temperature, dissolved oxygen (DO), and biochemical oxygen demand. The models were calibrated to field data collected from July to September 1994. Scenarios illustrated the impact of the tunnel on salinity, temperature, and DO under three flow conditions. In the worst case, impact of the tunnel on DO and temperature was short-lived and of limited spatial extent. Impact of the tunnel on salinity was indiscernible.