Albuquerque's Environmental Story

Educating For a Sustainable Community

Albuquerque's Natural Environment

Valley Flood Plains

  1. TERRAINS - Broad flat valley bottom, grading southward parallel to Rio Grande at about 0.1%. Natural slopes do not exceed l%; minor local relief between old terraces, swamps. Man-made relief features (streets, canals) are dominant.
  2. CLIMATE AND AIR QUALITY - Description: semiarid bordering on arid climatic conditions. Mean annual precipitation 7-8 inches (18-20 cm.); mean annual air temperature 53-54 F (12 C); frost free season 165-185 days. Comments: extreme temperature ranges; greater evapotranspiration rate; high incidence of cold air drainage and local inversions. An air quality problem area.
  3. GEOLOGY - The top 75 feet (23 m.) of the floodplain consists of recent alluvial fill from the Rio Grande; below that is much older fill of the Santa Fe Formation. Resources and Hazards: principal resources are ground water, adobe soil, and farmland. Main hazard is flooding.
  4. SOILS - Association: Gila-Vinton-Brazito. Description: level to gently sloping, well-drained loams of the Rio Grande floodplain. Notable Characteristics: principal hazards are shallow water table, flooding, and ditch back sloughing. Good to excellent development potential for all categories. 20% is saline or alkaline.
  5. drawing of a craneHYDROLOGY - Tthe Rio Grande is a braided, slightly meandering river which flows at an elevation above the floodplain. Drainage in the latter is largely internal, or by man-made ditches. The river is fed mainly by melt water from the northern New Mexico mountains. The floodplain proper receives flow from the local arroyos; flooding now being brought under control by diversions and holding ponds in the "Valley Sides" unit. Ground water is very shallow, fed by river seepage and percolation of irrigation water; the latter is diverted in large amounts from the Rio Grande. Alluvium forms an upper aquifer up to 120 feet (37 m.) thick; water is hard and frequently polluted. City wells in the Santa Fe Formation below obtain abundant water of good quality. Numerous domestic, commercial and irrigation wells also occur and local draw down effects are pronounced.
  6. VEGETATION - Zone: Upper Sonoran grading slightly into Lower Sonoran; Bosque along water courses. Indicator Species: alkali sacaton, inland salt grass, four wing salt bush; trees include cottonwood, Russian olive, and salt cedar. Productivity; Sensitivity: good natural and agricultural productivity; average alfalfa yield, the main crop, is 4.7 tons (11.6 MT per hectare) per acre. Highest natural productivity occurs where ground water is more plentiful.
  7. WILDLIFE - Indicator Species: ducks, shorebirds, muskrat, beaver, skunk, roadrunner, Norway rat. Also some fish and many reptiles and amphibians are common. Value: used as flyway for migratory birds; provides breeding sites, feed, and cover for grassland and aquatic species; locally rare wetland habitats for riparian woodland creatures.

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