The McMillan Delta is a broad, almost flat plain of sediment formed by the Pecos River entrance to McMillan Reservoir. The delta varies in width from 1.5 to 3 miles. McMillan Dam, in the Carlsbad Project, about 14 miles north of Carlsbad, was constructed in 1893 by private interests and rehabilitated by the Bureau of Reclamation in 1908. Reclamation completed Brantley Dam downstream, breached McMillan Dam, and drained McMillan Reservoir in 1991.