Wards Island STP Semi-Annual Compliance Report, Jan-Jun 2002

NYC 9/11 Public Portal Document

REMOVAL OF LAKE OVERFLOWS

A limited water management investigation was begim under the Lake Overflow Investigations Task (14) of the Wards Island SSES. This investigation included both Central Park and Van Cortland Park. Overflows from these lakes were measured, and alternatives to remove these overflows from the Wards Island combined sewer system were developed and evaluated. However, it was determined that further, more detailed analyses would need to be performed in order to reach a final recommendation.

A twenty-four month Engineer Services Contract has been awarded to Malcolm Pimie, Inc. to expand upon these preliminary investigations. All major waterbodies within Central Park (the Reservoir, the Pool, Harlem Meer, the Lake, Belvedere Lake, Conservatory Pond and the Pond), and Van Cortlandt Park (Van Cortlandt Lake and the 4 Henry Hudson lagoons) will be studied. Drainage areas of each individual water body will be delineated, stormwater outfalls discharging into these waterbodies will be identified, non-point runoff sources will be investigated and City water inputs will be determined. In addition, flow from existing wells and groundwater sources will be identified and quantified. A Water Quality model will be developed in order to predict water quality conditions and assist in the selection of the most favorable alternative for the diversion of flow from the Wards Island combined sewer system. In consultation with the Department of parks and Recreation (NYCDPR) and the Central Park Conservancy (CPC) for Central Park, a plan will be selected and an environmental assessment and conceptual design of that plan will be undertaken for each park.

UPDATE AS OF JUNE 2002;

While a recommended plan for Van Cortlandt Park is agreed upon in concept, further work has been deferred until such time as the new City administration canbe apprised of the status of this project. NYCDPR is unable-to- participate in funding the-Van Cortlandt-Park project at this-time; and although NYCDEP is prepared to move forward with components of the plan to reroute stormwater out of the collection system and to the Harlem River, NYCDPR is withholding their consent to let DEP do work in the Park until issues regarding the rest of the plan are resolved. The Central Park Conservancy, the organization that is responsible for the management of Central Park, has not approved the Central Park plan. Similar to the Van Cortlandt Park plan, the Central Park plan will need to be reviewed by the new administration prior to making decisions on implementation.

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