Success Reining in Proposed DFCs

Environmental Stewardship, Groundwater, Simsboro Aquifer

WaterDefenders make significant progress reining in Proposed Desired Future Conditions

GMA-12 votes against Lost Pines’ Conservation DFC

Figure 1. Graphic provided to the Lost Pines Board of Directors to demonstrate the concerns and requests from WaterDefenders Coalition (November 8, 2021, based on Scenario S-15)

We want to thank the Lost Pines Board of Directors for taking a strong stand in its recent vote to adopt conservation based Desired Future Conditions (DFCs) for the Simsboro aquifer. At the November 30th GMA-12 meeting we were able to confirm that the District will be able to adopt DFCs that are 10% more conservative for all aquifers as soon as they get certification back from the Texas Water Development Board that the adopted DFC are administratively complete, that their is agreement on the results of the pumping file, and Modeled Available Groundwater has been calculated for each aquifer.

Here is a brief summary of what happened over the last month.

After a major victory for conservation and consideration of domestic/livestock wells and surface waters by Lost Pines GCD Board (see below), the Groundwater Management Area 12 (GMA-12) representatives  voted against Lost Pines’ request at the November 12th meeting.

With the recent victory in hand, WaterDefenders went to the November 12th meeting hoping that all the member districts of GMA-12 would accept the “reasonable” actions taken by Lost Pines. However, we ended up with a decision by GMA-12 representatives that is a compromise.

General Manager, Jim Totten, made a motion to accept a pumping file [Scenario S-20] which would results in a new DFC of 183 feet average drawdown and about 30,300 acre-feet per year of pumping in the Simsboro formation for Lost Pines GCD.  While the motion was seconded by Post Oak Savannah GCD, it failed on 2-3 vote, yay-nay.

A second motion was made to accept a pumping file [S-19] which results in a new DFC of 240 feet average drawdown, and about 82,800 acre-feet per year (AFY) of pumping in the Simsboro formation for Lost Pines GCD. This motion passed 4-1, yay-nay.

However, this is a significant victory for WaterDefenders, stakeholders, landowners and surface waters in Lost Pines District.   Overall, this leaves us substantially ahead when compared to the Scenario S-12 that was initially proposed.  The reductions gained through WaterDefender efforts will result in a 54% reduction in pumping from the originally proposed DFC, and a 31% reduction in drawdown from the originally proposed DFC.

Final Adjustments to drawdowns will further reduce impacts

Fortunately, there are adjustments to the adopted drawdown values that can be made for both the Simsboro and other aquifers that will result in even less impact on domestic wells and surface waters. The final “desired future conditions,” expressed as average drawdown, can be adjusted up/down by a maximum of 10% by a district. And thankfully, these variances are not subject to a vote by other GMA-12 representatives. Lost Pines GCD can reduce the 240 feet average drawdown in the Simsboro down to 216 feet average drawdown representing about 56,500 acre-feet per year (AFY) of pumping; a 54% reduction in pumping from the originally proposed DFC. Also, in May of this year, GMA-12 adopted a DFC of 313 feet average drawdown in the Simsboro formation. A reduction to 216 is close to 100 feet less than the DFC proposed in May of this year; a 31% reduction in drawdown from the originally proposed DFC.

Given the concern expressed by Lost Pines GCD board for wells in the Carrizo, hopefully a 10% reduction will be made in the Carrizo, as well.

Major Victory for Conservation at Lost Pines’ Board Meeting

In a major victory for stakeholders, domestic well owners and the Colorado River, the Lost Pines Groundwater Conservation District Board passed the conservation option desired future conditions(DFC) for the Simsboro aquifer at the November 8, 2021, meeting.  The WaterDefenders coalition requested the conservation option after earlier guidance on DFCs failed to provide the cut-back in proposed pumping the board had expected.  The graphic on the right demonstrates WaterDefenders’ concerns and request.
WaterDefenders were supported in their request by  members of the public — many of whom were landowners with domestic wells and/or springs.– who made excellent comments to the board prior to the board’s discussion and vote. Click here for Environmental Stewardship’s comments.
After a long and tough discussion lead by Phil Cook around his motion, and with the assistance of Melissa Cole in bringing clarity, the motion was passed by the board in a 6 to 3 vote, with one seat vacant.
  • Paraphrasing the motion: The Board advises the General Manager to adopt district DFCs for the Simsboro aquifer that remain at 30,300 acre-feet per year (AFY), the same amount of pumping that was adopted in the 2017 DFCs. This requires adopting a drawdown that is about 183 ft.
  • [Note:  the above motion was analyzed in the Groundwater Availability Model Scenario S-20 which was presented to GMA-12 at the November 12, 2021 meeting]
As you can see in the graphic below, the DFC adopted for the Simsboro aquifer, at 30,300 AFY, is about 50,000 AFY less than what was proposed by the General Manager. This level of pumping is within the range of pumping that will be minimally protective of surface waters such as the Colorado River, its tributaries, seeps and springs, and greatly reduces the number of wells damaged.

Figure 2. Desired Future Conditions in Lost Pines District expressed ad averaged drawdown (ft).

Figure 3. Desired Future Conditions in Lost Pines District expressed in pumping (AFY).

 

The graphic on the left (Figure 2) shows the Desired Future Conditions (DFCs) in the aquifers in Lost Pines GCD expressed in average drawdown (ft).  A 10% variance in Scenario S-19 in the Simsboro aquifer is shown by the “allowed variance” line.   The same is true for the Carrizo aquifer.   The graphic on the right (Figure 3) shows the DFCs n the aquifers expressed as groundwater pumping (acre-feet per year, AFY).   Thought the drawdown numbers (Figure 2) for the Simsboro aquifer are the same for 2017 (blue) and S-19 (green), the amount of pumping (Figure 3) varies significantly.   the same is true for the Carrizo aquifer.  Note:  This difference is due to the change from the old Groundwater Availability Model having been improved and updated in 2018 to be more accurate (keep in mind all models are wrong, some are, however, more useful).  The S-19 and S-12 scenarios were running in the updated model.

Figure 4. Groundwater discharge to the main stem of the Colorado River using pumping files S-12 and S-19. The horizontal dotted line is where the river changes from being a “gaining” stream, to a “losing” stream where the river changes its historic relationship with the aquifers and starts contributing water to the aquifers on an on-going basis.

The graphic above (Figure 4) is from the updated Groundwater Availability Model.  One of the major revisions to the model was to make it more useful (more accurate) than the old model in predicting the impact of groundwater pumping on surface water resources like the Colorado River.   As you can see, both scenarios S-12 and S-19 cause the relationship of the river to change from its historicly “gaining” relationship, where the aquifers contribute groundwater to the Colorado River in the Bastrop reach of the river, to become a “losing” stream where the river starts contributing water to the aquifers on an on-going basis. Environmental Stewardship, and many hydrogeologists, consider this to be an unreasonable affect on the river.

WaterDefenders’ Requested DFCs (Figure 1)

There was a critical discussions on setting desired future conditions (DFCs) for the Simsboro aquifer at the October 20, meetings.  In that meeting Environmental Stewardship and Simsboro Aquifer Defense Fund provided a conservation option for consideration at the upcoming November 8th meeting. The graphic above describes what the WaterDefenders Coalition is requested (on the left) versus what the General Manager proposed (on the right).

For reasons detailed below, WaterDefenders requested that the Lost Pines board vote to approve no more than 30,303 acre-feet per year [AFY] of pumping in the Simsboro formation with a predicted average drawdown in water level of 183 feet. [see Figure 1 above]

At the September 2021 meeting, the Lost Pines board agreed to proposed average drawdown in water levels for other formations of the Carrizo-Wilcox and in the Sparta and Queen City aquifers. At the same meeting, in response to research presented by WaterDefenders, the Lost Pines board directed staff to research reductions in predicted average drawdown in the water level for the Simsboro formation. At the November 9th meeting, Director Phil Cook, tried to pass a motion that would have rolled all of the other aquifer levels back to the 2017 DFC levels. That motion failing, and at the request of other directors, he revised the motion to only apply to the Simsboro aquifer.

The Simsboro formation, part of the Carrizo-Wilcox aquifer, is important for many reasons; the Simsboro has high water quality; it is the focus of several large permits by water marketing companies hoping to sell water to other parts of Texas; and it has a major impact on the Colorado River and adjoining formations, the Calvert Bluff and the Hooper.

Currently, the Carrizo-Wilcox aquifer contributes approximately 21,000 AFY of water to the Colorado River. [Note: Lake Bastrop’s capacity is 15,000 acre-feet. The Carrizo-Wilcox aquifer contributes more than the equivalent of Lake Bastrop to the Colorado River each year!]. Research by Environmental Stewardship shows that when you increase groundwater pumping in the Carrizo-Wilcox, approximately 63% of the water collected is redirected away from the Colorado River, and other surface waters, toward the water pumps.

The current Desired Future Conditions, set in 2017, envision an increase in pumping up to approximately 30,303 AFY from the Simsboro formation by 2070. This amount of pumping will reduce the inflows to the Colorado river, down from 21,000 AFY to approximately 8,500 AFY. Environmental Stewardship believes this is the bare minimum needed for the Colorado River to survive another drought-of-record like we saw in 2011.

An Economic Impact Study by SAWDF estimates that 30,303 AFY of pumping will damage more than 250 domestic/livestock wells in Lee and Bastrop counties, including wells in the Calvert Bluff or Hooper formations. The economic impact for landowners with domestic/livestock wells, including mitigation costs, lost property value and lost income is conservatively estimated at $100,304,878. [see Figure 2]

In October 2021, Lost Pines’ staff introduced a new pumping file [S-15] for the Groundwater Availability Model [GAM] with proposed pumping of 82,839 AFY in the Simsboro formation. This pumping would have resulted in a predicted average drawdown of 239 feet by 2070. This is an increase of 2.7 times the pumping envisioned in the 2017 Desired Future Conditions.

Environmental Stewardship estimates that the Colorado River will become a “losing stream” when pumping in the Simsboro formation exceeds approximately 78,000 AFY; a conservation red-line. The pumping proposed by staff exceeds this threshold and robs the river of another 1,000 AFY. In a future severe drought, there would be little or no groundwater flowing to the river to retain its ecological resilience in support of fish, wildlife, irrigation, or recreation.

SAWDF reviewed the proposed pumping and updated the Economic Impact Study. SAWDF estimates the increased pumping will damage more than 500 domestic/livestock wells in Lee and Bastrop counties. The economic impact for landowners with domestic/livestock wells, including mitigation costs, lost property value and lost income is conservatively estimated at $155,526,151. [see Figure 2 below]

Due to the unreasonable impacts on surface waters, especially the Colorado River, property rights in groundwater, and damage to domestic/livestock wells, WaterDefenders.org requested that the Lost Pines board vote to approve no more than 30,303 AFY of pumping in the Simsboro formation with a predicted average drawdown in water level of 183 feet