The Water Use and Conservation Bureau, represented by Molly Magnuson and Julie Valdez, were tasked with “finding the quantity of water needed for the proposed expansion….”
The Cloverleaf Trust, doing business as the Riverbend Hot Springs, currently has 15 hot-springs bathing pools and wants to add eight more, applying for a new appropriation of 400 AFY about two years ago. The water would be pumped from an exploratory well drilled four years ago that is 240 feet deep.
Magnuson and Valdez used three different methods for evaluating how much water the Riverbend would need for the eight new pools.
Asked to rationalize how it arrived at 400 acre feet a year in its application, Cloverleaf states the eight new pools will each hold 748.1 gallons for a total of 5,984.8 gallons. With a “47-minute refresh rate” for each of the pools over an 18-hour day, the math works out that each pool will need 48.39 acre feet a year. In total, 387.12 acre feet a year are needed for the eight pools, with 13 more acre feet a year needed for “cold day contingency.”
The first method Magnuson and Valdez used to calculate how much water the Riverbend needs for the expansion was the “heat-factor method.” Using Cloverleaf’s calculation that the flow rate of the exploratory well is 39.6 gallons per minute, they estimated the eight pools would need 319 acre feet a year versus Cloverleaf’s 387 AFY calculation.
The difference between the OSE and Cloverleaf calculations are the number of hours the Riverbend operates. Magnuson and Valdez said the Riverbend’s web site shows it is open 8a.m. to 10 p.m., which is 14 hours. They added one hour to fill the pools in the morning, for a 15-hour fill-and-refresh time period to keep the pools hot. According to the Cloverleaf’s hydrologist, Jim Witcher, the pools are emptied and cleaned each night. Magnuson and Valdez claim Cloverleaf’s calculation assumes the pools operate 24 hours a day.
The second method used was the “capacity method. Again using Cloverleaf’s 39.6 gallons-per-minute flow rate and 47-minute refresh rate, Magnuson and Valdez shorten Cloverleaf’s 24-hour-a-day variable to 14-hours-a-day, claiming Riverbend needs 316 acre feet a year for the expansion.
The third method used was the “proportion method.” Magnuson and Valdez propose drilling into the shallow hot springs aquifer to meet the expansion needs, which is how the 15 current pools operate—from shallow wells.
“Using a ‘Proportion’ method,” Magnuson and Valdez found “that adding 8 wells would require approximately 96 acre-feet per annum shallow groundwater if the wells were used during current business hours based on the amount of water currently used for the demands of the business.”
Magnuson and Valdez arrived at 96 acre feet per year by looking at the Riverbend’s metered water readings. They said the actual water used for the 15 pools in operation was 105 acre feet in 2018.
They claim the Riverbend give a “calculated use” of 345 acre feet a year is needed to fill and keep the current 15 pools hot. But in actuality, the Riverbend uses about “30 percent of the calculated use,” Magnuson and Valdez state.
With little explanation, Magnuson and Valdez therefore assume the eight new pools will only use about one-third what Cloverleaf is applying for, or 96 acre feet a year from the shallow, not the deep hot springs basin.
Laura Petronis, of the OSE’s Hydrology Bureau also evaluated Cloverleaf’s 400-acre-feet-a-year application.
Petronis estimates the drawdown 400 acre feet a year of pumping from the Cloverleaf’s exploratory well will have on the Rio Grande and the first 40 feet or shallow part of the hot springs aquifer, which is sandy soil with some clay “lenses.”
In 10 years the Rio Grande would be depleted of 389.42 acre feet. In 40 years the Rio Grande would be depleted of 396.73 acre feet. In 100 years the Rio Grande would be depleted of 398.39 acre feet, Petronis said.
For wells in the Hot Springs basin, Petronis said 15 wells would be “critical,” that is, their senior water right would be “unacceptably” affected by 400 acre feet a year of pumping from the Cloverleaf exploratory well, according to her pumping model and calculations.
However, Petronis excluded 10 of those wells from her model. Nine wells “are not completed” or not in use, she said. And a well owned by TorC Properties, one of several protestants in the case, is excluded because “it is uncertain if this well has been deepened.” Evidently the lack of information on the depth of the well precluded Petronis from putting it in the pumping model.
The remaining five wells are owned by two other protestants to the Cloverleaf application. The Martin Family Trust, doing business as the Artesian Bath House, owns three of the wells, which are not pumped, but come up under their own pressure. The other protestant, Meleasa Malzahn, president of La Paloma Hot Springs and Spa, owns two wells which also are not pumped, but well up under natural pressure.
According to Petronis’ model, the Artesian wells would drop 8.1 feet over 40 years of pumping 400 acre feet a year at the Cloverleaf well. If the whole commercial water right is exercised, that is if 514 acre feet a year is pumped, the drawdown would be 16.6 feet in 40 years.
La Paloma’s wells would drop 1.3 feet if 400 acre feet a year is pumped and 5.1 feet if 514 acre feet a year is pumped over 40 years, Petronis states.
Because of the drawdown to the river and the critical wells, Magnuson and Valdez and Petronis all recommend that the Cloverleaf’s 400 acre-feet-a-year application be denied.