ALBANY — Attorney General Eric Schneiderman officially joined the “fracking” fight yesterday with a lawsuit accusing the feds of advancing the controversial gas-drilling technique without the necessary reviews.

Schneiderman said the Army Corps of Engineers flouted the National Environmental Policy Act and risked the drinking water of millions of New Yorkers with regulations that could spur new natural-gas wells in the Delaware River watershed.

Horizontal hydraulic fracturing — or fracking — could potentially unlock a 100-year supply of natural gas.