HB 1728 Hawaii House · 2026 Regular Session

RELATING TO RAINWATER CATCHMENT SYSTEMS.

Summary

Requires the counties to allow for the installation and operation of rainwater catchment systems for potable and nonpotable uses on all properties. Allows the counties to require registration, inspection, or notification of rainwater catchment systems. (CD1)

Bill status signed all 5 stages cleared

Introduction

Jan 2026

Committee Review

Apr 2026

House Passage

May 2026

Senate Passage

May 2026

Signed into Law

Jul 2026

Introduced Jan 20, 2026 Signed Jul 9, 2026

Maddy AI version diff · 3 comparisons

What changed between versions

HB1728_HD1 → HB1728_SD1 · 3 edits

MINOR

This bill shifts the authority for regulating rainwater catchment systems from local counties to the state Department of Health. Instead of each county setting its own rules, the Department of Health will now create uniform statewide standards, including specific safety and design guidelines based on national industry standards.

Scope change

The bill's scope changed from a local-level program where every county independently managed rainwater systems to a centralized state-level program. The Department of Health now has exclusive authority to permit, regulate, and enforce standards for these systems across all properties in Hawaii.

ENFORCEMENT

Authority to permit and regulate rainwater catchment systems was transferred from county governments to the Department of Health.

REQUIREMENT

The Department of Health is now required to adopt specific rules based on national standards (ARCSA/ASPE/ANSI 63 and ASSE/ARCSA/IAPMO/ANSI Series 21000) for system design, installation, and personnel qualifications.

The definition of rainwater catchment systems was updated to remove hyphens in compound words like 'non-potable' and 'non-potable use' to align with standard spelling conventions.

Floor votes

How they voted

This bill passed the Senate by voice vote (no roll call recorded).

Full legislative history

Actions timeline

Total actions

Key actions

Committee

Amendments

May 6, 2026

Lower · Passed

Passed Final Reading as amended in CD 1 with none voting aye with reservations; none voting no (0) and none excused (0).

lower

May 6, 2026

Upper · Passed

Passed Final Reading, as amended (CD 1). Ayes, 25; Aye(s) with reservations: none . 0 No(es): none. 0 Excused: none.

upper

Apr 29, 2026

Introduced

48 Hrs. Notice (as amended CD 1) 05-06-26

upper

Apr 29, 2026

Upper · Passed

Reported from Conference Committee as amended CD 1 (Conf. Com. Rep. No. 84-26).

upper

Apr 29, 2026

Lower · Passed

Reported from Conference Committee (Conf Com. Rep. No. 84-26) as amended in (CD 1).

lower

Apr 29, 2026

Lower · Passed

The Conference Committee recommends that the measure be Passed, with Amendments. The votes were as follows: 3 Ayes: Representative(s) Hashem, Tarnas, Souza; Ayes with reservations: none; 0 Noes: none; and 0 Excused: none.

lower

Apr 29, 2026

Upper · Passed

The Conference committee recommends that the measure be PASSED, WITH AMENDMENTS. The votes of the Senate Conference Managers were as follows: 3 Aye(s): Senator(s) Wakai, San Buenaventura, Fevella; Aye(s) with reservations: none ; 0 No(es): none; and 1 Excused: Senator(s) Lee, C..

upper

Apr 27, 2026

Upper · Passed

Conference committee meeting scheduled for 04-29-26 10:50AM; Conference Room 325.

upper

Apr 16, 2026

Amended

House disagrees with Senate amendment (s).

lower

Apr 14, 2026

Introduced

Returned from Senate (Sen. Com. No. 614) in amended form (SD 1).

lower

Apr 14, 2026

Upper · Passed

Report adopted; Passed Third Reading. Ayes, 25; Aye(s) with reservations: none . Noes, 0 (none). Excused, 0 (none). Transmitted to House.

upper

Apr 7, 2026

Upper · Passed

The committee(s) on JDC recommend(s) that the measure be PASSED, UNAMENDED. The votes in JDC were as follows: 4 Aye(s): Senator(s) Rhoads, Gabbard, Chang, San Buenaventura; Aye(s) with reservations: none ; 0 No(es): none; and 1 Excused: Senator(s) Awa.

upper

Apr 1, 2026

Upper · Passed

The committee(s) on JDC will hold a public decision making on 04-07-26 10:15AM; Conference Room 016 & Videoconference.

upper

Mar 30, 2026

Upper · Passed

Report adopted; Passed Second Reading, as amended (SD 1) and referred to JDC.

upper

Mar 30, 2026

Committee

Reported from EIG/WLA (Stand. Com. Rep. No. 3258) with recommendation of passage on Second Reading, as amended (SD 1) and referral to JDC.

upper

Mar 19, 2026

Upper · Passed

The committee(s) on EIG recommend(s) that the measure be PASSED, WITH AMENDMENTS. The votes in EIG were as follows: 5 Aye(s): Senator(s) Wakai, Chang, DeCoite, Richards, Fevella; Aye(s) with reservations: none ; 0 No(es): none; and 0 Excused: none.

upper

Mar 19, 2026

Upper · Passed

The committee(s) on WLA recommend(s) that the measure be PASSED, WITH AMENDMENTS. The votes in WLA were as follows: 4 Aye(s): Senator(s) Lee, C., Chang, Lamosao, DeCorte; Aye(s) with reservations: none ; 0 No(es): none; and 1 Excused: Senator(s) Inouye.

upper

Mar 16, 2026

Upper · Passed

The committee(s) on EIG/WLA has scheduled a public hearing on 03-19-26 3:00PM; Conference Room 224 & Videoconference.

upper

Mar 12, 2026

Committee

Referred to EIG/WLA, JDC.

upper

Mar 12, 2026

Introduced

Received from House (Hse. Com. No. 273).

upper

Mar 10, 2026

Lower · Passed

Passed Third Reading with Representative(s) Iwamoto voting aye with reservations; none voting no (0) and none excused (0). Transmitted to Senate.

lower

Mar 4, 2026

Lower · Passed

The committee on JHA recommend that the measure be PASSED, UNAMENDED. The votes were as follows: 8 Ayes: Representative(s) Tarnas, Poepoe, Hashem, Kahaloa, Sayama, Takayama, Garcia, Shimizu; Ayes with reservations: none; Noes: none; and 2 Excused: Representative(s) Belatti, Cochran.

lower

Feb 11, 2026

Committee

Reported from WAL (Stand. Com. Rep. No. 200-26) as amended in HD 1, recommending passage on Second Reading and referral to JHA.

lower

Feb 3, 2026

Lower · Passed

The committee on WAL recommend that the measure be PASSED, WITH AMENDMENTS. The votes were as follows: 9 Ayes: Representative(s) Hashem, Morikawa, Belatti, Ichiyama, Poepoe, Woodson, Souza; Ayes with reservations: Representative(s) Iwamoto, Shimizu; Noes: none; and Excused: none.

lower

Jan 26, 2026

Committee

Referred to WAL, JHA, referral sheet 1

lower

Jan 21, 2026

Introduced

Introduced and Pass First Reading.

lower

Jan 20, 2026

Introduced

Prefiled.

lower

19 primary · 1 co-sponsor