The City desires to make changes that result in higher long-term aquifer levels, protecting water quality and safeguarding against drought.
Current permit conditions for ASR operations can negatively impact the Equus Beds.
Current permit conditions result in recharge water being withdrawn early during drought, or short dry spells, and will result in lower aquifer levels.
The change will allow the City to save recharged water until as late as possible during a drought, and would maintain higher aquifer levels overall.
The aquifer is full right now, doesn’t this ensure that we don’t reach 1993 levels?
The current near-natural full aquifer condition is a result of recent years that have been wetter than normal. Use of the aquifer by both Wichita and agricultural users was reduced, resulting in a natural recovery.
It is anticipated that future droughts might follow normal years, after water use has lowered the aquifer.
How does the City know that reaching the 1993 levels will happen during drought?
Modeling the effects of extended drought on the aquifer indicates that groundwater levels will fall below levels observed in 1993. The predictive groundwater model used was originally developed by the US Bureau of Reclamation and recently updated by the United States Geological Survey.
The proposed permit modifications could prevent this from happening because higher aquifer levels would be maintained during short dry periods.
How do the requested ASR Minimum Index Levels compare to the condition of the aquifer in 1993?
In the City’s wellfield area, the aquifer was approximately 88% full during the lowest levels of the 1993 drought period. The requested levels represent an average of over 80% full conditions.
The average increased depth to water is 12.8 feet.
What impact will this have on chloride intrusion within the ASR project area?
Wichita’s water resource management plan is centered on the preservation of groundwater and has resulted in significant recovery of water levels within the project area, thus slowing the intrusion chloride plume into the wellfield.
Strategic use of recharge credits only during extended drought will continue to slow the chloride intrusion into the ASR project area.
Will ASR Phase I recharge wells be included in the requested modification?
No, a primary objective of ASR Phase I was to slow the chloride intrusion from the Burrton area. This remains an objective today; as such, the City does is not including a request to modify the operating conditions of the ASR Phase I facilities.
How will this impact other users of groundwater within the ASR project area?
Other groundwater users in the area will continue to benefit from the increased groundwater levels within the ASR project area as a result of more flexible ASR operations project and Wichita’s outcome based approach to water resource management.
The City has proposed provisions that will protect domestic well owners. If the water quality at a domestic well degrades, the City will supply water that meets the drinking water standards.