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Terrill Yazzie, Rio Grande Project, 3/3/2012

Problem: How do we conserve the Rio Grande?

The problem area: see map.

Figure 1
Figure 2
The problem of the Rio Grande can extend to more than just the river itself and local terrestrial banks. A geological aspect may add to the problem.
Figure 3
The greatest channel width is at river mile 110. Why?

There are problems with sediment, reduction in peak spring run-off flows, armoring of banks and point bars, and establishment of non native phreatophyte forests. The current condition greatly favors non-native, water consuming, phreatophyte species. Additionally, certain segments of the Socorro Reach are experiencing a depravity of sediment, while others (south of Bosque Del Apache NWR) are experiencing excessive sedimentation problems.

Please see Technical Memorandum from The Bosque Hydrology Group.

Phreatophytes have biological value as being used as biofilters. They are plants of great ecological value, fast growing pioneers and highly resistant to disease. They make excellent fodder for livestock and provide nesting areas and shelter for fauna. They are used as fuel, cheap construction material, and basketry. Many of the plants grow in degraded waters, salty or saline, that are useless for agriculture. Phreatophyte plants help to purify these waters and their roots fix heavy metals with a bacteria filter.

Large communities of Phreatophytes along the Rio Grande are the natural filters that add value to the quality of the water.

Figure 4

This Graph shows discharge in the southern part of the river in Texas/Mexico.

What about the northern part of the River's Discharge Profile? Please see Rio Grande Reservoir Storage Conditions.

Invasive plants
Tamarisk/saltcedar (Tamarix chinensis), Russian olive (Elaeognus angustifolio), and Siberian elm (Ulmus sp.) result from human caused changes provide favorable conditions to grow. These plants out compete the native cottonwood. The Tamarisk has a year round seed production, while the Russian olive and Siberian elm sprout in the shady area's under the cottonwoods. A low cottonwood population causes a decrease nesting sites for birds such as woodpeckers and nuthatches.

Please see Tamarisk info.

Crickets were the primary detrivore that are adapted to the flooding and liked moist organic matter. Now that it is dry, the job is taken over by pillbugs and woodlice that like the drought.

The House sparrow and European starling take over woodpeckers nesting territory.

Bullfrog is an omnivore devours everything.

Native species compete with introduced species. Of the 27 species of fish that were historically native to the Rio Grande in New Mexico, only 14 remain (Cowley, 2006). One of the greatest problems for the fishes of the Rio Grande Basin is the dewatering of the river channel, which occurs when the irrigation season coincides with periods of drought.

Please see New Mexico Museum of Natural Science and History.

Table 2

Scientific Name Common Name Native MRG LRG Canals LRG Drain Canals
Family Clupeidae Shads  
Dorosoma cepedianum Gizzard shad N X X X
Dorosoma petenense Threadfin shad     X  
Family Cyprinidae Minnows  
Cyprinella lutrensis Red shiner N X X X
Cyprinus carpio Common carp   X X X
Hybognathus amarus Rio Grande silvery minnow N X X X
Pimephales promelas Fathead minnow N X X X
Pimephales vigilax Bullhead minnow   X X X
Platygobio gracilis Flathead chub N X X X
Rhinichthys cataractae Longnose dace N X X X
Family Catostomidae Suckers  
Carpiodes carpio River carpsucker N X   X
Catostomus commersonii White sucker   X    
Catostomus plebeius Rio Grande sucker N X    
Family Ictaluridae Catfishes  
Ameiurus melas Black bullhead   X    
Ameiurus natalis Yellow bullhead     X X
Ictalurus furcatus Blue catfish N X    
Ictalurus punctatus Channel catfish   X X X
Family Salmonidae Trouts  
Oncorhynchus mykiss Rainbow trout   X    
Family Centrarchidae Sunfishes  
Lepomis macrochirus Bluegill N X   X
Lepomis megalotis Longear sunfish   X X X
Lepomis hybrids Sunfish hybrids       X
Lepomis cyanellus Green sunfish   X   X
Micropterus salmoides Largemouth bass   X   X
Micropterus dolomieu Smallmouth bass   X   X
Pomoxis annularis White crappie   X X X
Pomoxis nigromaculatus Black crappie   X   X
Family Perchichthyidae Basses  
Morone chrysops White bass     X X
Family Percidae Perches  
Perca flavescens Yellow perch   X    
Sander vitreus Walleye   X X X
Family Poeciliidae Livebearers  
Gambusia affinis Mosquitofish N X X X
      40% 28% 32%

Based on the data given here, the ratio of native fish to non-native in the MRG is 40%, the LRG canal is 28%, and the LRG Drain Canals is 32%. Attacking the problems of maintaining native fish populations to substantiate the Rio Grande could be addressed by a plan to increase LRG native fish population, and the solution could positively impact the LRG Drain canals.

The Rio Grande is a river has an ecosystem that evolved around major flooding about every 5 years. There are about ten dams on the Rio Grande that disrupt the flood processes. The decrease of water flow in the Rio Grande disrupts the river flow that causes narrowing of the flood plain. This results in an increase of area of the bank that allows the increase of vegetation-sediment problems (starvation below San Acacia, excess sediment below 380 Bridge due to Elephant Butte Reservoir). No high spring run-off peak flows.

Please see Technical Memorandum from The Bosque Hydrology Group.

Data about the reservoirs show that Falcon, Elephant Butte, and Caballo are increasing in storage capacity. Amistad is the only one declining with use.

Please see Rio Grande Reservoir Storage Conditions.

Questions: What factors are affecting Amistad decline?

Maps of the Dams on the Rio Grande

Figure 5
Figure 6

Please see Rio Grande Basin Conditions.

How fast is the bank increasing?


Human induced problems include agriculture, pumpage, mining, and urbanization.

Irrigation Channels


Irregular Shapes - Landscapes are often designed with many irregular shapes that do not match the options available for sprinkler head patterns. Although those shapes can be quite attractive, they result in inefficient use of water through over-spray onto fences, rocks, etc.

Soil Conditions - Poor top soil, deficient in organic material or severely compacted causes many lawn problems including a shorter lifetime for your lawn. Often these lawns look good at first year but the roots do not develop well and there is poor percolation and drainage. Soil amendments are available as well as aeration, and thatching. Sometimes it is best to start over with good topsoil.

Shade or Full Sun - How much water your plants need is greatly affected by how warm the air is around them. Areas in full sun will need more water than otherwise calculated --- areas with significant shade will need less. If either of these conditions exist, adjust your watering volumes as appropriate.

Mowing Frequency and Height of Lawn - A shorter lawn will need more water than one with taller grass since the taller grass helps shade the roots and keep the moisture in.

Back Flow Preventers - A back flow preventer is essential to protect your inside water for cooking and washing from contamination with outside water in the event of a sudden change in water pressure.

Old or Broken Irrigation Systems - Problems with older systems include:

  • Broken heads can result in geysers - high volume of water lost quickly - runoff, drop in pressure
  • Mismatched heads - rotors, pop-ups, drip on the same line
  • Wrong heads, for example, needs to be a quarter circle but it's a half circle
  • Misaligned - not watering what it should be watering - usually creates fugitive water
  • Too much pressure creates significant misting; Too little pressure results in some areas not getting enough water (brown spots).
  • Spacing - too close together or too far apart or leaky heads - reduce performance

New Technologies

Sprinkler Heads - Traditional sprinkler heads deliver water fast (1.5"/hr). Two traditional problems: (1) The ground can only absorb water at the rate of .3" - .5"/hr. (2) Misting due to fine spray. Newer heads pop-up, but have multi-stream rotors rather than thin spray and they provide slow watering (.4"/hr.) to match the absorption rate of your lawns soil. These heads are pressure matched to deliver water with greater uniformity than traditional heads (efficiency of about 80% vs. 70%). The WUA offers rebates for these new multi-stream heads.

Controllers (timers) - New generation has many more options, easier to program and can add rain sensors.
Please see: Irrigation System Issues.

The Nomenclature of Irrigation Canals in New Mexico

Canal Type Other Names in Use Purpose

Canal aka Main canal, lateral, ditch. Purpose: Deliver water from the acequia, acequia madre, Rio Grande to water users conveyance canal

Drain aka canal Drain, clear ditch Drain Purpose: excess water from fields; prevent waterlogging of soils by intercepting shallow groundwater; provide flood protection

Return canal aka Waste way Purpose: Return water from the irrigation system to the Rio Grande

Study by Sallenave et al states that the study indicated that irrigation canals are great refugee for fish during drying periods.
Please see Fishes in the Middle and Lower Rio Grande Irrigation Systems of New Mexico by Rossana Sallenave, Carl Carrasco and David E. Cowley.

Quality of Water

Non-point sources such as increase of septic tanks, residual minerals from evapo-transpiration, urban run-off, and wide spread application agricultural chemicals.

Point sources are oil and gas reservoirs both natural and manmade that leak, metal and minerals from mining and milling, nitrate from dairies, sewage treatment plant, explosive manufacturing, other industrial facilities, septic tanks, and landfills.

Please see Rio Grande Valley Study at USGS.


Most of the precipitation that falls in the valleys is lost to evaporation and transpiration, and little water percolates to a depth sufficient to recharge the basin-fill aquifers. The rate of precipitation recharge is affected by many factors, including quantity and duration of precipitation, soil-moisture content, rate of evapotranspiration, topography, soil permeability, and depth to ground water. Estimated rates of precipitation recharge are essentially zero in areas subject to a combination of little precipitation, substantial evapotranspiration, steep land surface, relatively impermeable soil, and deep water table. In a few areas, primarily in stream valleys with highly permeable soil and shallow depth to water, precipitation recharge may exceed 0.2 inch per year.

Please see Aquifer Basics at USGS.

Figure 7

Why is Municipal going to increase?

That growth in population will fuel increased demand for water for municipal purposes: drinking, hygiene, lawns and gardens, recreational use, etc. Municipal water demand, now about 230,000 acrefeet per year (AF/yr), is projected to swell to almost 626,000 AF/yr. (An acre-foot of water equals 325,581 gallons.) The vast majority of the water available to the region - more than 94 percent - comes from supplies stored in the Amistad and Falcon reservoir system.

The Texas Water Development Board has estimated that unmet water needs could have considerable socioeconomic impacts on region: more than $2 billion lost to decreased sales, $2 billion in lost income, more than 26,000 lost jobs, and more than $75 million in lost taxes by 2060.

Please see the document from the Rio Grande Regional Water Planning Group.

Problem county areas along the Rio Grande

Figure 8
Proposed Solutions to Conserving the southern Rio Grande:

(In progress)