The high concrete and stone brick Gilboa Dam in Schoharie County was completed in 1926. Over time the dam eroded to where it posed a potential threat to those living downstream. In December 2005, the New York City Department of Environmental Protection began a $24 million project to bring the dam up to New York State safety standards. Beginning in December 2006 eighty post-tensioned anchoring cables were installed through holes drilled in the dam into bedrock below, bringing it up to New York State safety standards. During this overhaul, residents nearby complained that their tap water had turned a brownish color, perhaps due to the intense drilling into the earth to anchor the dam.