Proposed Desired Future Conditions & Modeled Available - PowerPoint PPT Presentation

Proposed Desired Future Conditions & Modeled Available Groundwater GMA 1 Joint Planning Committee Meeting April 20, 2016 Steven D. Walthour, PG

Ogallala Aquifer Proposed Desired Future Conditions  40 % of volume in storage remaining in 50 years, for the period 2012 - 2062 in Dallam, Hartley, Moore, and Sherman counties;  50 % of volume in storage remaining in 50 years, for the period 2012 - 2062 in Hansford, Hutchinson, Lipscomb, Ochiltree, Carson, Donley, Gray, Roberts, Wheeler, and Oldham Counties; and within Panhandle District Armstrong and Potter Counties;  80 % of volume in storage remaining in 50 years for the period 2012 - 2062, in Hemphill County;  The total average drawdown is approximately 20 feet in 50 years for the period 2012 -2062, in Randall County and within High Plains District in Armstrong and in Potter Counties.

Dockum Aquifer Proposed Desired Future Conditions  Average drawdown in water levels will be no more than forty percent (40%) in 50 years for the period 2012 -2062 in Dallam, Hartley, Moore and Sherman Counties;  Average decline in water levels will be no more than thirty feet (30’) in 50 years for the period 2012 -2062 in Oldham, Carson, and within Panhandle District in Armstrong and in Potter Counties;  The total average drawdown is approximately 40 feet in 50 years for the period 2012 -2062, in Randall County and within High Plains District in Armstrong and in Potter Counties.

GMA 1 JPC Meetings November 8, 2011 August 19, 2014; August 9, 2012; November 6, 2014; February 18, 2015; July 23, 2013; August 23, 2015; November 7, 2013; February 25, 2016; February 21, 2014; March 17, 2016; and April 11, 2014; April 20, 2016 May 30, 2014;

Groundwater Availability Models  Conceptual Model for the High Plains Aquifer System Groundwater Availability Model;  Numerical Model for the High Plains Aquifer System Groundwater Availability Model;  Six HPAS GAM Predictive Runs – Intera;  HPAS GAM Predictive Runs – Hutchison  TWDB Predictive Runs for TERS  Previous GAM Predictive Runs

HPAS GAM Predictive Runs April 6, 2016 -Ogallala Aquifer. With the exception of HPWD, targets were based on fraction remaining after 50 years (in 2062), specifically NPGCD-west (0.40), NPGCD-east (0.50), PGCD (0.50), and HCUWCD (0.80). In HPWD, targets were based on average drawdown, corresponding to pumping rates set at 150% of 2012 pumping rates.

HPAS GAM Predictive Runs April 6, 2016 -Dockum Aquifer. Targets were set as a fraction of available drawdown in NPGCD-west (0.40). In the other districts, Dockum targets were based on average drawdown after 50 years (in 2062). Specifically, PGCD (30’), HPWD (40’), Oldham County-No GCD (30’), Randall County – No GCD (40’)

HPAS GAM Predictive Runs April 6, 2016  2016.5 - saturated thickness was set to 30 feet.  2016.6 - saturated thickness was set to 10 feet.

All Aquifers Modeled Available Groundwater (afy) Predictive Runs 5.3-5.5 County 2015* 2016 2020 2030 2040 2050 2062 2070 Armstrong 8,739 64,977 66,677 63,484 58,784 53,887 48,164 44,573 Carson 129,743 181,421 192,729 184,371 170,535 153,936 134,257 121,673 Dallam 314,346 416,274 402,753 301,372 240,382 181,080 117,202 79,219 Donley 39,476 69,404 75,012 76,288 73,162 67,872 60,901 56,275 Gray 41,540 171,475 181,601 175,267 163,099 148,713 131,744 121,136 Hansford 169,191 276,822 275,769 272,655 271,968 270,280 269,478 269,128 Hartley 355,566 524,608 473,654 344,196 282,545 220,441 153,135 118,632 Hemphill 21,935 55,176 52,338 52,217 52,409 52,305 52,340 52,358 Hutchinson 64,870 103,110 95,244 95,694 94,418 92,372 90,580 89,357 Lipscomb 39,006 55,112 267,540 266,710 267,370 266,591 266,556 266,546 Moore 171,652 248,949 229,630 186,323 152,348 116,127 76,940 55,670 Ochiltree 84,963 115,225 244,446 243,931 244,670 244,050 244,085 244,094 Oldham 14,903 152,169 174,075 169,031 154,361 137,402 118,352 108,866 Potter 8,846 48,050 56,170 55,156 51,742 47,889 43,386 40,527 Randall 46,817 31,785 36,096 37,960 36,825 34,584 31,575 29,528 Roberts 79,284 359,716 431,798 455,129 428,388 390,246 342,747 311,054 Sherman 289,327 365,074 399,273 349,021 282,589 212,871 136,867 93,930 Wheeler 13,534 114,844 130,782 138,810 137,761 132,311 123,308 116,837 TOTAL 1,893,738 3,354,191 3,785,587 3,467,615 3,163,356 2,822,957 2,441,617 2,219,403 2015 rates are identical to the last year of the calibrated model (2012) except in NPGCD where other rates were provided by NPGCD staff.

All Aquifers Modeled Available Groundwater (afy) Predictive Runs 6.3-6.5 County 2015* 2016 2020 2030 2040 2050 2062 2070 Armstrong 8,868 65,608 67,527 64,240 59,394 54,310 48,461 44,845 Carson 129,854 181,476 192,787 184,425 170,583 153,977 134,292 121,706 Dallam 321,378 421,179 411,047 300,571 243,089 185,490 121,997 89,095 Donley 39,491 70,819 76,925 78,237 74,944 69,493 62,383 57,704 Gray 41,540 171,664 182,087 175,968 163,729 149,267 132,280 121,649 Hansford 169,191 276,822 275,769 272,655 271,968 270,280 269,478 269,128 Hartley 355,662 525,609 476,633 338,937 280,271 220,614 154,877 120,493 Hemphill 21,935 55,302 52,549 52,432 52,600 52,474 52,490 52,498 Hutchinson 64,870 103,460 95,942 96,614 95,271 93,191 91,319 90,021 Lipscomb 39,006 55,112 267,540 266,710 267,370 266,591 266,556 266,547 Moore 171,702 249,517 230,251 186,912 152,873 116,605 77,361 56,033 Ochiltree 84,963 115,225 244,446 243,931 244,670 244,050 244,085 244,094 Oldham 16,594 153,944 176,803 172,065 157,531 140,882 122,165 112,174 Potter 9,286 48,681 56,903 55,880 52,408 48,525 43,993 41,111 Randall 47,130 31,785 36,096 37,966 36,871 34,642 31,612 29,555 Roberts 79,284 359,716 431,798 455,129 428,388 390,246 342,747 311,054 Sherman 289,327 365,074 399,273 349,047 282,665 213,012 137,012 94,033 Wheeler 13,711 116,334 133,554 141,727 140,359 134,609 125,426 119,017 TOTAL 1,903,792 3,367,327 3,807,930 3,473,446 3,174,984 2,838,258 2,458,534 2,240,757 2015 rates are identical to the last year of the calibrated model (2012) except in NPGCD where other rates were provided by NPGCD staff.

Factor 1 – Uses & Conditions  2011 Panhandle Regional Water Plan (2012 State Water Plan)  2016 Panhandle Regional Water Plan  Projected Exempt Groundwater Use Estimates - TWDB, December 2015  Ogallala Aquifer, Seymour Aquifer, And Total Pumping For Municipal, Manufacturing, Mining, Steam Electric Power, Irrigation And Livestock Uses For 2004-2013 TWDB.  Minor Aquifers, Other Aquifers And Unknown Aquifers Pumping For Municipal, Manufacturing, Mining, Steam Electric Power, Irrigation And Livestock Uses For 2004-2013 TWDB.  HPAS GAM Predictive Runs 5.3-5.5  HPAS GAM Predictive Runs 6.3-6.5

Ogallala DFC - Dallam, Hartley, Sherman, and Moore Counties  High agriculture usage of the aquifer,  Above average rate of decline,  Very limited stream flow, and  High agriculture economic impact.  Combined counties projected use approximates the average MAG under both predictive runs

Ogallala DFC s - Armstrong, Donley, Carson, Gray, Hansford, Hutchinson, Lipscomb, Ochiltree, Oldham, Potter, Randall, Roberts, and Wheeler, Counties;  Moderate agriculture usage of the aquifer,  Significant municipal well fields in the area,  Average rate of decline,  Minimal stream flow, and  Moderate agriculture and municipal economic impact.  Projected use is below to well below the average MAG under both predictive runs

Ogallala DFC - Hemphill County  Minimal agriculture usage of the aquifer,  Minimal rate of decline,  Extensive stream flow for the planning area, and  Water related ecotourism economic impact.  Projected use is well below the average MAG under both predictive runs

Dockum DFC – Dallam, Hartley, Moore, Sherman Counties  Currently minimal use compared to Ogallala  Primarily confined aquifer conditions  Minor to no recharge  Very limited to no discharge to springs, rivers, draws, and escarpments.  Potentially high to supplementary agriculture economic impact.  Historic use below average MAG under both predictive runs.

Dockum DFC – Armstrong, Carson, Oldham, Potter, Randall County  Currently minimal use compared to Ogallala  Confined and Unconfined aquifer conditions  Minor recharge in all but Carson County.  Limited to significant discharge to springs, rivers, draws, and escarpments.  Potentially high to supplementary agriculture economic impact.  Historic use below average MAG under both predictive runs.