Cuenca Alimentadora del Distrito Nacional de Riego 004 Don Martín, also known as CADNR 004 Don Martín, is a protected natural area in northern Mexico.

It protects portions of the upper watershed of the Salado River and its tributaries, including the Sabinas, Alamós, and Mimbres rivers, which drain the eastern slope of the Sierra Madre Oriental.

[1] CADNR 004 Don Martín is at the eastern edge of the Chihuahuan Desert, as it transitions to the Tamaulipan mezquital.

Oak and pine woodlands and forests occur at higher elevations in the Sierra Madre Oriental.

[2] A portion of the Sabinas River was designated a Ramsar site (wetland of international importance) on 2 February 2008.