Iowa Admin. Code r. 567-51.5
A permit for the withdrawal of groundwater for use as a heat exchange media in a heating/cooling system may be granted, allowing such groundwater to be discharged into sanitary or storm sewers (when the use is complete). However, a permittee that has such a system shall make plan and design provisions to the permittee's system to allow the groundwater to be returned directly (i.e., reinjected) to the aquifer from which it was originally pumped. The department reserves the right to order such direct return as part of its water conservation plan responsibility as described in 567-subrule 52.9(3) (chiefly incorporating mandated emergency conservation measures), and its priority allocation plan responsibility as described in 567-subrule 52.10(3).
Iowa Admin. Code r. 567-51.5