FLOOD04773

• County: Montezuma
• Community: Dolores & Montezuma County
• Stream Name: Dolores River
• Basin: San Juan/Dolores
• Title: Dolores River near Dolores, Colorado Flood Insurance Study
• Date: 5/1/2004
• Prepared For: Dolores
• Prepared By: US Army Corps of Engineers
• Floodplain - Doc Type: Floodplain Report/Masterplan

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From their respective headwaters, both forks llow southwesterly through narrow canyons

with a dense riparian overstory of deciduous vegetation. Downstream of the confluence, the

Dolores River flows 14.6 miles through a deep canyon to the city of Dolores. Routing reaches arc

discusst.-d in more detail in Section 6.7 and stream profiles arc plotted on Plate 3,

Lost Canyon Creek enters the Dolores River at the downstream end of the city of Dolores.

From its headwaters above 10,000 feet in the La Plata Mountains. Lost Canyon Creek travels in a

westerly direction 106,920 feet approximately 31 miles downstream at Dolores. The terrain is

undulating. Vegetation is mostly sagebrush and Pinon.junipcr. with timber above 9,000 feet. The

Dolores River flows into McPhee Dam, which is 10 miles north\vest from the town of Dolores in

Montezuma County, Colorado.

McPhee Dam and Reservoir was authorized by the Colorado River Basin Act of

September 30,1968 (Public Law 90-537), as a participating project under the Colorado River
Storage Act of April II, 1956 (public Law 84-485). Construction was completed in 1983 and
lilling of the Reservoir began in March 1984. The dam is owned by the U,S. Bureau of

Reclamation (USBR) and operated by the Dolores Water Conservancy District under the

supervision of USBR. The dam was operated for flood control under the supervision of the U.S.

Anny Corps of Engineers from 1984 until 1994. The dam is now operated to provide water for

irrigation. municipal and industrial use, hydropower, recreation, and fish and wildlife. Its

capacity at gross pool is 381.200 acre-feet (Reference 4-g, Water Control Manual, and Pertinent

Datasheet, included here as Appendix B, Document 2). Of the major tributaries discharging into

McPhee Reservoir. among them Lost Canyon, Plateau, House, and Beaver Creek. the Dolores

River is its major contributor.

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