How Much Land Is Enough? N.Y.C. Ends Buying Spree of the Catskills.

The largest single taxpayer in the Catskills is New York City.

To protect its drinking water — 90 percent of which comes from Catskills watersheds — the city spent nearly three decades accumulating 156,350 acres of forest and fields. It’s an area larger than all the land in Brooklyn, Queens, the Bronx, and Manhattan combined.

The idea was to keep human and agricultural waste out of the drinking water, so that the city could get a waiver on filtering it from the Environmental Protection Agency. Filtration would have been prohibitively expensive: an estimated $8 billion to build the facilities, and $500 million annually to maintain them.

Instead, the city and a group of Catskills communities negotiated an agreement that secured the EPA waiver. The city would fund local water-quality projects, like the construction of sewage treatment plants, but it would also be allowed to solicit and purchase properties to protect the water supply. Beginning in 1997, the city spent $518 million to assemble a vast patchwork of parcels, mostly in the northern half of the mountains.

For the towns, it was an uneasy accord. Many residents were unhappy that the city could buy almost any land it wanted, as long as the owner was willing to sell. And though the upgrades to their sewer and septic systems improved quality of life, and the tax revenue from city-owned land became critical for local budgets, much of the scarce developable land in the area was put off-limits, restricting the communities’ options for much-needed residential and commercial expansion.

Now the buying spree is over.

Last fall, the city quietly agreed to wind down most of the so-called Land Acquisition Program (it will keep the land it has already purchased). An independent review of the program by the National Academies, commissioned by the city’s Department of Environmental Protection, had concluded that the majority of further land purchases would be of little benefit, since most of the available properties contribute little pollution to the water supply.