RYE, N.Y. – Rye residents will have to wait for the dredging of the Upper Pond at Bowman Avenue Dam, the Flood Committee announced, citing inconclusive data of the maximum volume the dam can handle before an overflow.
“Until data is verified and vetted, the committee will not go ahead with the project,” Committee Chair Rafael Elias-Linero told the Rye City Council Wednesday night.
Water flows and water volumes are the main factor in determining the impact of a flood. The committee compared flood mitigation documents dating back to 1979 and determined the results of topography studies vary too greatly on the volume capacity of the basin. Recent study results show higher water volumes than previous reports. Elias-Linero recommended gathering more data to reconcile any discrepancies in previous reports.
A dredge is included in the city’s 2012-2016 Capital Improvement Plan at a ticket price of $10.6 million, funded through grants and aid. The project was initially slated to begin this year and to be completed by 2014.
The committee suggested the town assess the benefit of installing two or three additional monitoring gauges at around $15,000 to $20,000 each to give more accurate data. If proposed, these gauges could be included in the November bond.
While more data is collected, Elias-Linero suggested the city also look at alternatives in addition to dredging in the future. “We already know dredging is not going to be enough,” he said.
An alternative would be to increase or elevate the wall at the dam, as the dam will be up for review and must meet new state regulations that were put in place to ensure all dams can protect downstream communities and the environment.
If the dam is raised by two feet, the basin’s storage capacity could increase by about 148,000 yards, which has a greater impact than any of the suggested dredging projects. Elevating the dam might cost an estimated $1.5 million, according to Elias-Linero.
In response, Mayor Douglas French said, “Let’s keep working at it and see what our options are.”