Please Reject Renewable #Water Resources Proposal — The #Alamosa Citizen – Coyote Gulch

ERIC Harmon is the kind of person Douglas County says they want to listen to.

He is a hydrogeologist specializing in the aquifers of the San Luis Valley of the Upper Rio Grande Basin. In fact, his team has completed the groundwater component of the Rio Grande Decision Support System, which is generally described in state water court documents as “an interactive computer system that uses data and computational models to help decision makers solve unstructured problems”. The RGDSS is what the state relies on to determine the impact of groundwater pumping.

Harmon is also retired and did not participate in any of the presentations the three Douglas County Commissioners heard about renewable water resources and his pitch to Douglas County to partner in Valley Export. of San Luis.

What does Harmon’s experience and expertise say about the RWR proposal? He wrote a letter to the Douglas County Commissioners outlining his concerns and recommending that Douglas County reject the RWR proposal. He has not yet heard from the commissioners. Alamosa Citizen also asked Douglas County for a response to Harmon’s letter.

Hydrogeologist Eric J. Harmon

“The Renewable Water Resources (RWR) proposal to Douglas County to use ARPA funds should be rejected in favor of less risky projects,” Harmon told the commissioners. “The RWR project would place undue risks on San Luis Valley (SLV) water users and ratepayers (water customers) in Douglas County. Why? For that, we need to tackle the weeds on the SLV aquifers.

You can read the letter HERE.

Harmon said he testified in Division 3 Water Court (San Luis Valley) in the AWDI case (1991), the Confined Aquifer New Use Rules case (2006), the Great Sand Dunes In-Place Groundwater Right (2008) and Groundwater Rules Case (2018).

“Confined aquifer testing in the SLV by my test team was done as part of Colorado’s Rio Grande Decision Support System (RGDSS) in the early 2000s,” he said. to the commissioners. “Our tests have repeatedly shown that pumping impacts travel very rapidly outward from a confined aquifer well, often causing drawdown (drop in water level) up to ½ mile in a day. following the start of the pump. At several locations, pumping from a deep well caused measurable drawdown in layers much shallower than the pumping area. This is how confined aquifers work: the drawdown spreads very far, very quickly. SLV’s confined aquifer is “leaky”.

After sending his letter to for publication, we asked him some additional questions. The exchange is below:

AC: What concerns or thoughts, if any, can you share about the drought the San Luis Valley has experienced since 2002?

HE: Conditions are never static in hydrology. The dynamic nature of water, weather patterns and the hydrological cycle mean that conditions are constantly changing. But where there is a long-lasting drought, the work of scientists and engineers becomes more difficult. This means that any predictions we are asked to make may be less reliable than we would like, because we don’t always have similar historical conditions to which we can go back and compare ourselves.

AC: Flow measurements documented by Davis Engineering for the Rio Grande Water Conservation District show disturbing patterns. Have you looked at these throughput metrics recently? In your opinion, what kind of impact is drought, climate change having on the basin and should this be a concern with the RWR proposal?

HE: I tried to follow general hydrological trends in the valley, including snow accumulation and stream flow. I have also been following trends in unconfined aquifer storage change that Davis Engineering has done for RGWCD for many years. It is clear that even after a number of years of self-imposed pumping reductions in sub-districts, there is still too little water available to meet irrigation demand and to replenish the storage deficit. groundwater in the unconfined aquifer of the closed basin. If drought or climate change persists in the future, as seems likely, then those impacts should be of concern in any further water appropriation, whether by RWR or anyone else.

AC: Would changing conditions, continuing drought, declining snowmelt, especially along the Sangre de Cristo range, be a factor in a legal proceeding?

HE: Decreasing snow cover, earlier and faster runoff, and continued drought are certainly of concern in the Sangre de Cristos, as they are in the San Juans. Throughout the valley, the water supply of the Sangres is considerably lower than that of the San Juans. Smaller drainage areas, the “rain shadow” effect of the San Juans before snowstorms reach the Sangres, and differences in topography and geology between the two ranges are all factors. If asked, I would advise the water tribunal to consider all of these factors very carefully. If groundwater recharge is lower in the future than predicted, this will almost certainly have an impact on the injury issue.

AC: Commissioner Teal said at the last meeting (March 8) that Douglas County had heard several times that there was a “million acre feet” of water in the SLV Aquifer. How to approach this concept?

HE: I find no reference to a “million acre-feet” in the RWR proposal or in the submissions to Douglas County. RWR said 22,000 acre-feet per year, the amount they intend to pump, represents 2.5% of the annual aquifer recharge. Thus, the RWR number for annual recharge is 880,000 acre-feet. I don’t know if that’s what Commissioner Teal is referring to. What matters, however, is not the annual groundwater recharge or the volume of groundwater stored in the aquifer. The important thing is that the water resources of the Valley are over-appropriated. As Colorado Division of Water Resources officials have pointed out, this means there is no water available for appropriation and a full (“1 for 1”) replacement is required. under the rules.

Source link

Comments are closed.