156-29 Bosquecito Water Table and Hydric Soils Study.



Monday, October 17, 2011
Henry Gonzalez Convention Center, Hall C, Street Level

Kenneth F. Scheffe, National Soil Survey Center, USDA-NRCS, Lincoln, NE, James Bauchert, Wyoming State Office, USDA-NRCS, Casper, WY and Aaron Miller, Santa Fe MLRA Soil Survey Office, USDA-NRCS, Santa Fe, NM
A  groundwater and hydric soil indicator study is being conducted by USDA-NRCS near Bosquecito in Socorro County, New Mexico in partnership with the U.S. Army COE and the US-EPA .This study supports on-going interagency field-testing of the Arid West Wetland Delineation Manual.

 The hydrology of the Rio Grande and its associated bosque (riparian forest) has been altered to varying degrees by flood protection and irrigation systems. These structures modulate peak stream flow during spring snowmelt and from monsoonal storms thus affecting the duration and frequency of overbank flooding.

 Data is being gathered to determine the interrelationship between surface and groundwater in these hydric soils and wetlands relative to the use of “Field Indicators of Hydric Soils of the United States version 7.0, 2010”.   

 Near-surface groundwater monitoring wells and piezometers were installed with soil moisture and temperature sensors and are being monitored with data logging systems validated bi-weekly with observations since July 2010. 

After one year of monitoring, the following relationships were observed regarding the water table at Bosquecito:

a) Water table depths year-round are highly correlated to stream gage height of the Rio Grande showing a direct, though tempered, response to fluctuations in stream height;

b) There appears to be little, if any, influence of local upland groundwater recharge to the water tables;

c) Hydric soils have thus far only been determined to exist in those soils that currently meet a hydric indicator;

d) The study area was anomalously dry for the water year, experiencing the lowest precipitation on record. Additional/continued monitoring is needed to draw conclusions for a typical year. 

e) Data collected during this extreme period may be useful in development of an analog model of future water table response under long-term conditions of unstable climatic swings.

See more from this Division: S10 Wetland Soils
See more from this Session: General Wetland Soils: II (Includes Graduate Student Competition)