Under the provisions of IDAPA 58.01.08, Idaho Rules for Public Drinking Water Systems, a water main extension, whether approved for construction by the Department of Environmental Quality (DEQ) or by a qualified licensed professional engineer (QLPE), is a material modification to the public water system. The current rules also specify that all portions of the existing system that are affected by the water main extension must be in compliance with the rules in effect at the time the project is reviewed and approved.  This requirement could in some cases require upgrades to existing parts of the water system to meet criteria for pumping redundancy, standby power, fire flow, and other applicable rule requirements such as completion of a facility plan.

The objective of this rulemaking is to modify the recently updated Idaho Rules for Public Drinking Water Systems so that the engineering community can approve simple water main extensions as intended by 2005 Senate Bill 1220 and as codified at Idaho Code § 39-118.  The proposed rules define a simple water main extension as a new or replacement water main(s) that is connected to existing water main facilities and does not require the addition of system components designed to control quantity or pressure, including, but not limited to, booster stations, new sources, pressure reducing stations, or reservoirs; and continues to provide the required pressure and quantity for the system. 

The following list sets out the major issues included in the proposed rules:

1. Add and/or revise definitions (Section 003) and revise rule sections as necessary;
2. Clarify Section 500, Demonstration of Technical, Financial, and Managerial Capacity;
3. Revise Section 501, General Design Requirements for Public Drinking Water Systems;
4. Modify the content of facility plans and preliminary engineering reports contained in Sections 502 and 503, respectively;
5. Revise Section 504, Review of Plans and Specifications;
6. Clarify separation requirements for sources of contamination from public drinking water wells (Sections 510-512, and 900);
7. Modify sections regarding spring sources and ground water sources (Sections 513 and 514);
8. Clarify Section 531, Design Standards for Chemical Application;
9. Add and clarify design requirements for drinking water distribution systems (Section 542);
10. Further define storage structures and facilities (Section 544); and
11. Clarify several operating criteria for public drinking water systems (Section 552).

This proposed rule also includes any necessary corrections that are typographical and nonsubstantive in nature (e.g., making corrections for consistency with other sections in this rule chapter, IDAPA 58.01.16, Wastewater Rules, and other DEQ rules).  These changes were made based on feedback from the regulated community and DEQ staff who routinely use the rules.

After consideration of public comments, the rule has been revised at Sections 511, 514, 531, 542, 544, and 552.  The remainder of the rule has been adopted as proposed.