It flows 7 miles (11 km) from springs at the foot of Winter Ridge through high desert, range, and wetlands before emptying into Summer Lake.

The Ana River is located a few miles east of the small unincorporated community of Summer Lake, Oregon.

As a result, runoff from snow melt and overland drainage is minimal except during major thunderstorms that produce direct precipitation on areas immediately adjacent to the river.

[3][5] The Ana River originates in a series of springs located east of Winter Ridge, a high basin and range escarpment.

Approximately 7 miles (11 km) from its source, the Ana River empties into the north end of Summer Lake.

In 2005, the Oregon Department of Fish and Wildlife joined with the United States Department of Agriculture's Natural Resources Conservation Service, Ducks Unlimited, Oregon Hunters Association, and the North American Wetlands Conservation Council to enhance approximately 1,000 acres (4.0 km2) of seasonally flooded wetland habitat in the River Ranch area of the Summer Lake Wildlife Area.

The project replaced a series of diversion structures along the Ana River that supply water to the adjacent wetlands.

The project significantly improved the efficiency of the water management system, benefiting both the river and wetland habitats.

Common animals in the Ana River area include Nuttall's cottontail, black-tailed jackrabbits, yellow-bellied marmot, chipmunks, Belding's ground squirrels, California ground squirrels, long-tailed weasels, mink, raccoons, striped skunks, mule deer, coyotes, and bobcats.

In the dry high desert country along the upper Ana River, California quail and mourning doves are very common.

Both species of Tui chub are found throughout the Anna River system and provide an important food source for a wide variety of mammals and birds as well as other fish.

Hybrid striped bass are sterile so the Oregon Department of Fish and Wildlife stocks the river with approximately 2,000 fingerings every two years.

[9][12] The Ana River provides a wide variety of recreational opportunities including fishing, birdwatching, wildlife photography, hunting, and camping.

Rainbow trout range in size fingerings to over 20 inches (510 mm), and the hybrid bass can reach 18 pounds (8.2 kg).

[6][9][17] In fact, the Oregon state record hybrid bass, weighing 18 pounds and 9.5 ounces, was caught in the Ana Reservoir in 2009.

This wetland area hosts hundreds of thousands of birds during the annual spring and fall Pacific Flyway migrations.

Because of the large numbers and variety of birds that use the wetlands and surrounding meadows, the Ana River area is popular for birdwatching and wildlife photography.

[2][14][15][16] Hunters can find a wide variety of waterfowl, upland birds, and big game in the Ana River area.

During hunting season, the Summer Lake Wildlife Area opens two hours before sunrise and closes a half-hour after sunset.