Fort Valley Ecosystem

Project Scope

Landscape Character

The Rio de Flag, a small ephemeral stream which supports perennial riparian vegetation, has carved a shallow canyon through the area from its sources on the surrounding slopes. Little Leroux Spring, Big Leroux Spring, Taylor Spring, and Chimney Spring all feed into the Rio de Flag.

A large open grassland dominates the central part of the planning area and includes most of the private, developed lands within the planning area. The grassland is encompassed by a forest of young and middle-aged ponderosa pine trees, which forms a fairly homogenous monoculture throughout most of the forested Fort Valley area. Most of the public land within the project area is pine forest. The pine forest is interspersed infrequently with clumps and stringers of aspen, and with small mountain meadow grasslands.

Wildflowers, such as sunflowers and flax in the prairie grassland and iris, lupine, and penstemon in the mountain meadow grasslands occur in drifts and large masses during the spring and summer. The ephemeral watercourses and springs have associated areas with riparian vegetation including willow, alder, and some aspen, which contrasts with the predominant conifers, especially in the fall. The northeast corner of the planning area, which is on the slope of Agassiz Peak, rises in elevation above the rest of the planning area and includes mixed conifer and aspen stands.

Elk are by far the most common and visible wildlife, aside from a variety of birds. Other wildlife, such as deer and turkey exist in the area but are less visible.

Euro-American settlement and the associated resource use, played a major role in the development of Flagstaff, the transcontinental railroad, as well as the Forest Service. Historic remains on the landscape such as homesteads, cabins, camps, logging railroads, the Beale Wagon Road, the Grand Canyon Stage Route, and the Fort Valley Experimental Station are all tangible reminders of those early beginnings.

Range of Variability

The most visible elements of the natural landscape, the basic land form, water features and related plant life exist as they have for perhaps the last 10,000 years. Springs have been boxed and piped; the Rio and tributaries have been moved around by roads and development; grasslands and some stands have been occupied by houses and cut by roads; vegetative and fire patterns have been altered; and wildlife species have been extirpated and manipulated. But there is still a sense of naturalness over the extended area. The open grasslands, are the most visibly altered portions of the landscape. The edge of the great pine forest that covers much of the Flagstaff landscape can be seen from all houses and roads within the area. The mass of the San Francisco Mountain towers over the project area, dominating the view and shadowing most of the area every sunrise.

The natural elements of the area have been altered, but many of the pieces exist and would be recognized by a visitor from ancient times.

Water Quality

Standards for ephemeral stream channel apply to the reach of the Rio De Flag above the City of Flagstaff Wastewater Treatment Plant. This assessment is confirmed by A. Cajero ADEQ

Water quality studies related to the Flagstaff Watershed have not been done. The nearest monitoring point on the Little Colorado River is located over 50 miles downstream of the Fort Valley Area. Portions of the Rio De Flag drainage, downstream from the Upper Rio De Flag watershed, are dominated by effluent water from sewage treatment. The Rio De Flag is essentially constrained in the area of Continental Country Club, the Big Fill Lake area, and Sante Fe Railroad tracks. It is extremely rare that runoff from the Upper Rio De Flag watershed continues beyond this point. The Fort Valley Area and surrounding areas are the headwaters to the Rio de Flag. Because of generally satisfactory soil condition within the Upper Rio De Flag watershed, best management practices used during project implementation and absence of high quality perennial water, none of the alternatives will have a significant effect on water quality.

Downstream activity potentially impacts the Flagstaff 5th code watershed. The Flagstaff watershed is ultimately a tributary to the Little Colorado River. This watershed is further broken down into the Upper and Lower Rio De Flag, Sinclair Wash, and Wildcat watersheds.

The Fort Valley Area and surrounding areas are the headwaters to the Rio de Flag. For the ephemeral stream reach above the City of Flagstaff water treatment plant, the designated uses are Aquatic and Wildlife (A&We) and partial body contact (PBC).

Water Yield under Alternatives A, B, and D (slightly different levels of tree thinning, prescribed fire, road closures, restoration of grass, shrubs and forbs, and meadow restoration) will increase ground vegetation, but there will be little or no increase in water yield to the Rio de Flag. Alternative C (no action) is steadily decreasing water yield into the Rio De Flag as tree biomass increases.

Changes in soil and watershed conditions become significant as fire size and intensity increase. Wildfire can have major effects on vegetation, ground cover, and soil properties, resulting in reduced infiltration and increased overland flow. Intense wildfire can reduce soil surface resistance to erosion resulting in accelerated soil erosion, particularly because of heavy summer precipitation. Peak discharges are likely to increase because of wildfire, and water quality is likely to decrease due to increased sediment loads.