Committee approves updated injection-well rules; prohibits new agricultural drainage injection wells

The House Resources and Conservation Committee on Feb. 6 approved revised administrative rules governing Class 5 injection wells, the Idaho Department of Water Resources said during the hearing.

Eric Bowe, Water Compliance Bureau chief and rules regulation officer for the Idaho Department of Water Resources, told the committee the rulemaking “offers a set of procedures and minimum standards for the construction and use of injection wells to ensure that they are constructed and operated in a manner that is protective of the ground water resources and public health.” He told members the changes are needed to maintain state primacy for regulation of Class 5 injection wells under the federal Safe Drinking Water Act and to align state definitions with CFR 144.1.

The pending rule reorganizes multiple sections for readability and modifies several definitions, including "endangerment" and "underground source of drinking water, USDW," to match federal language. The department said the substantive changes in the pending rule are concentrated in three sections and that the broader reformatting produced many strikeouts and underscored passages that relocate text without changing substance.

Representative Nelson questioned how the rule treats canal water versus agricultural runoff; Bowe and other staff explained that IDWR classifies a well subclass by the water source. If the source contains agricultural drainage it is a 5F1 well, even if the water travels through a canal. Bowe said the change that prohibited construction of new subclass 5F1 agricultural-waste injection wells is “less restrictive” language aligned with current practice; IDWR has not permitted a new 5F1 well since about February (year not specified in testimony).

The rule also adds definitions and standards referencing recycled-water rules (IDAPA 58.01.17) and creates a framework for injecting recycled water from municipal or industrial sources into aquifers, including exemptions for regulated subsurface land-application systems managed by the Idaho Department of Environmental Quality (DEQ). Jason Van Gilder, public works director for the City of Middleton, testified in support and said the changes allow municipalities to use subsurface drip irrigation to apply highly treated effluent on city property without seeking a waiver under the prior rule structure. “Updating the state's administrative rules in a way that protects our natural resources, protects our citizens, encourages innovation and adapts to new challenges while removing unnecessary bureaucracy and administrative red tape is exactly what 0-based rulemaking should be about,” Van Gilder said.

Representative Andrus and others sought clarification on where the department will apply source-protection time-of-travel zones for municipal drinking-water supplies; IDWR staff said public water systems prepare source-water protection documents that identify 0–3, 3–6 and 6–10 year time-of-travel areas used to evaluate risk to supplies.

Representative Anderson moved to approve the docket. The committee took a voice vote; the motion passed and the committee accepted the docket.

The committee record shows the department held five negotiating meetings and received more than 100 oral and written comments during the two-year rulemaking process. The department said the changes were made with input from the Idaho Department of Environmental Quality, hydrogeologists, engineers and other stakeholders.

What’s next: With committee approval the rule will proceed through the administrative process described by statute before final adoption and publication by the department.