A small earthquake southeast of Albany Wednesday prompted an immediate inspection of the Gilboa Dam under new operating procedures put in place by the New York City Department of Environmental Protection, an engineer said Friday.
The earthquake was minor and didn’t cause any damage to the massive concrete structure that remains the focus of a multimillion-dollar construction project now in its first phase, said John H. Vickers, chief of western operations for the DEP.
News of the DEP’s response to the earthquake was part of an update Vickers and other representatives from the DEP provided to the Schoharie County Board of Supervisors on Friday.
According to the Lamont-Doherty Cooperative Seismographic Network, the magnitude 2.4 event took place at roughly 11:20 p.m. on Wednesday, centered roughly 32 miles southeast of Albany.
People in the vicinity of a magnitude 2.4 earthquake would feel minor shaking lasting two or three seconds, according to Won-Young Kim, senior research scientist at the Lamont-Doherty Earth Observatory of Columbia University in Palisades, NY.
The New York City DEP was notified and immediately dispatched inspectors to ensure there were no problems, as part of new standard operating procedure, Vickers said.
The DEP in January approved a $7.2 million contract for the construction of a series of gates to be installed in the notch that was cut into the top of the dam’s spillway as part of earlier emergency work.
Work on staging that project has already begun but the DEP is waiting for permits before installing the gate system.
The DEP started planning major work, expected to cost $592 million, after engineers determined the 81-year-old dam didn’t meet modern standards.
A system of cables was installed through the dam and anchored to bedrock beneath it to ensure the structure won’t slide out of position in the event of massive flooding.
Vickers on Friday said the project remains on schedule. The DEP received 11 bids for the second phase of the project, which will cost $18.4 million, he said.
Phase II will include site preparation work in preparation for the major reconstruction and building a new access road to the west of the dam.
This phase will also include developing a new “discharge structure,” which will be enable engineers to release water from the Schoharie Reservoir through piping that will travel underground and around the dam and release the water downstream.
Though such a project would be several years down the road, the outlet of the discharge structure will be fitted to accommodate hydroelectric power generating equipment, Vickers said.
Members of a local citizens’ group organized to keep an eye on the dam’s integrity, called Dam Concerned Citizens Inc., attended Friday’s meeting and passed out a flier announcing their annual meeting date.
The 7 p.m. meeting will take place on Wednesday, March 25 at the Fultonham Union Church. The meeting will include a speech on regional rainfall trends by Dr. Robert Titus and an update on the Gilboa Dam rehabilitation project by Carl Davis of the New York City Department of Environmental Protection.