The results of water level measurements made during winter show an average decline of -2.56 feet in the groundwater levels of the Ogallala Aquifer within the 16-county High Plains Underground Water Conservation District No. 1 service area in 2011.
A review of available records in the HPWD archives at Lubbock, Texas has documented only two other years since the creation of the water district 61 years ago where recorded average water level declines were greater than those for 2011. In 1964, the average water level decline was -3.99 feet, and in 1966, the average water level decline was -2.92 feet.
That makes the average water level decline of -2.56 feet recorded for 2011 the third highest.
In addition, last year represents the largest decline recorded in the water district's observation well network in 25 years (1987 to 2012). The next largest decline for that 25-year period was -.2.15 feet recorded in both 1995 and 1999.
"The impact of exceptional drought and record-setting high temperatures were clearly documented by the HPWD 2011-2012 winter water level measurement program," says William F. Mullican, P.G., HPWD adviser for groundwater issues. "Extreme heat, low humidity, and hot, dry wind caused increased supplemental irrigation in both the agricultural and urban sectors."
The average water level decline of -2.56 feet was recorded in the district's network of 1,280 privately-owned water wells in 2001, which is significantly greater than the -0.05 of a foot recorded in 2010, an average rainfall year.
The 10-year average change in groundwater levels (2002-2012) was -0.81 of a foot, while the 5-year average change in groundwater levels (2007-2012) was -1.04 feet.
Average declines of more than three feet were recorded in six of the 16 counties within the HPWD.
"The HPWD Board of Directors and staff thank the many producers who continue to support the water level observation network by providing access to their wells for depth-to-water measurements each year," says HPWD Manager Jim Conkwright. "These data guide us in making decisions regarding management and conservation of groundwater resources within the district for future generations."