With the 1966 departure of the last 400 defectives, the Eastern Correctional Institution became the Catskill Reformatory. For the next three years, there was little change in the operation of the institution, though the census did not recover from the loss of the defectives.

By 1970, the state prison population was in steep decline; Napanoch, which had held steady at about 1,000 inmates for 35 years, was down to a little more than 500. NYS Governor Nelson A. Rockefeller and NYC Mayor John V. Lindsay entered into an agreement to house up to 2,500 prisoners serving city jail terms in several state institutions including the Catskill Reformatory. The state would provide the physical plant and the manpower, the city would retain legal custody of the prisoners and reimburse the state for operating costs. Catskill received its first NYC inmates on March 30, 1970 and within five months the switch was complete. . . . .

Since the State-City contract was in effect for only three years, staff never fully adjusted to the difficulties of administering a correctional program on behalf of another jurisdiction or to the short sentences (local jails hold inmates with sentences of up to a year; state prisons hold inmates serving terms of a year and more). The threat of parole denial as an inducement to behave lost its sting. Intake tasks now took up most program staff time: inmates arrived from Rikers Island without medical, dental, or psychiatric examinations; without educational levels determined; sometimes without commitment papers. Teaching staff could accomplish little during the average four to five month stay, and there was no time to train inmates for maintenance or industrial work.

In 1972, the state prison population reached its lowest point since the WWII. Then, fueled by baby boomers and the Rockefeller drug laws, the prison census began a long climb. The state needed Napanoch back. In March, 1973, Eastern New York Correctional Facility was again taking inmates sentenced to state prison terms.

Napanoch had undergone its final transition. Since 1973, ENYCF has served as a maximum security, general confinement facility for males 16 years and older.