Water

The proposed project poses potential adverse effects on lagoon water quality that are significant. These impacts would be caused by a number of activities, including demolition, grading, excavation, construction and bulkhead repair or replacement – all of which would result in the discharge of sediment – a pollutant -- into the lagoon. The sediment discharge would take the form of slumping or sloughing along the shoreline or under the waterline due to operation of heavy equipment, application of fill, pile driving, and bulkhead failure.

The slumping and sloughing could also negatively impact the stormwater retention capability of the lagoon, the depth of water at the property line, and the stability of existing buildings along the lagoon.

There is also a risk of increased contaminated surface water runoff from project grounds into the lagoon. Moreover, there is a concern that the partially subterranean parking structure may flood during significant rain events, resulting in further discharges of contaminated water into the lagoon. Such surface water runoff and discharges could impact the water quality of the lagoon and its sensitive ecosystem.