Middle Rio Grande, New Mexico

Reach Specific Restoration Constraints and Promising Features

Note: This list of reach specific restoration constraints and promising features was compiled from agency and university researchers working within the Bosque Initiative. The features have been placed in alphabetical order in order to eliminate a bias towards the importance of a given feature. This is a work in progress. Please e-mail comments to Paul_Tashjian@fws.gov

Middle Rio Grande in general:

Constraints

Bank stabilization by jetty jacks and non native vegetation

Loss of variability in peak flows

Narrowing of channel width to depth ratios from historic

Non native vegetation: salt cedar and Russian olives

Reduction of spring run off peak flow

See-saw affect of erosion in Pueblo/ABQ Reaches and aggradation in Isleta/ Socorro Reaches

(Sediment starvation high in system, unable to mobilize sufficient sediment low in system)

Promising features

Good seed source for native vegetation

Intact natural shape to hydrograph

Reservoir operation holds promise to time spring run off to native seed dispersal

System Issues

Non native vegetation control

1) Mechanical control

2) Chemical control

3) The need to consider beetle control

Pueblo Reach (Cochiti to Bernanlillo)

Constraints

armored, coarse grained channel

coarse bed material

depauperate sediment supply

disassociation of flood plain with flows

incised main channel

jetty jacks (below Angostora)

low width-depth ratio channel ratios

reduced spring run off peak

rip-rap

Russian Olives

threat of fire

Promising Features

lots of older cottonwood trees- great seed source

nice bosque environment

prevalence of meanders and oxbow lakes

sediment loading from side canyons

ABQ Reach (Bernalillo to Isleta Diversion)

Constraints

disassociation of flood plain with flows

jetty jacks

low width-depth channel ratios

reduced spring run off peak

reduced sediment supply

Russian Olives

salt cedars

stabilized banks

threat of fire

uniform width of channel (~200 meters)

Promising Features

alternating sand bars that can be cleared and leveled for flood ability

islands forming suggesting an increase in sediment supply

sediment loading from side channels

Isleta Reach (Isleta Diversion to to Rio Puerco confluence)

Constraints

dense floodplain vegetation

jetty jacks

natural levees

predominate disassociation of flood plain with flows

Russian Olive

salt cedar

stabilized banks

threat of fire

uniform width of channel (~200 meters)

Promising Features

alternating sand bars that can be cleared and leveled for flood ability

islands forming suggesting an increase in sediment supply

overbanking occurring within segments

Socorro Reach (Rio Puerco to Elephant Butte)

Constraints

fire threat

incised, straight segments with very low width-depth channel ratios

jetty jacks

low flow/ intermittency

natural levees

salt cedar reproduction during storm run off, during growing season with

rain

vertical bank accretion causing a narrowing channel

Promising Features

floodplain- river connectivity

dynamic bed

mixed age classes of native trees

overbanking occurring frequently

wide channel in segments