The encyclopedia · Strategy & Leadership · Strategic decision · 1997
New York protected its Catskill watershed instead of filtering its water
In 1997 NYC signed a watershed agreement — land purchases, farm rules, sewage upgrades — and EPA let its Catskill-Delaware water stay unfiltered.
NYC Department of Environmental Protection
the move
The Catskill-Delaware system supplies about 90% of New York City's drinking water from protected mountain reservoirs. Federal rules required filtration unless the city could prove its watershed stayed clean.
On 21 January 1997 EPA issued an interim Filtration Avoidance Determination tied to the signing of a multi-party watershed protection agreement among the city, state, EPA, watershed communities and environmental groups.
The agreement required aggressive land acquisition on a willing-seller basis, strict new watershed rules, upgraded sewage treatment against parasites such as cryptosporidium and giardia, limits on phosphorus, and farm and partnership programmes — while the city still had to keep designing a filtration plant as a fallback.
EPA issued a five-year FAD on 6 May 1997 and retained primacy over the system until 2007 to keep enforcement credible; the dual track meant protection had to work or filtration would be built.
why it works
- Source protection avoided the billions a filtration plant would cost.
- Willing-seller land purchases kept the deal politically workable.
- A dual-track fallback kept EPA's enforcement credible.
- Partnership programmes turned watershed towns into stakeholders, not opponents.
what transfers
When regulation offers a compliance choice, protect the asset itself: source protection avoids the capital cost and operating risk of end-of-pipe treatment, as long as the rules are enforced.
what came after
New York renewed the Filtration Avoidance Determination repeatedly (2002, 2007 and later) as long as watershed programmes continued; the Catskill-Delaware supply remains one of the largest unfiltered surface water systems in the United States.
references
- EPA Issues Interim Filtration Avoidance Determination To NYC For Its Catskill-Delaware Water System
- History of the New York City Watershed Filtration Avoidance Determination
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