---
type: "Bill"
title: "Sunset Process Weather Modification"
description: "Sunset Process - House Health, Insurance, and Environment Committee. Sections 1 and 2 of the bill continue the regulation of people who modify the weather until 2033. Section 3 repeals a provision that prohibits weather modification that benefits another state if the other state prohibits weather modification that benefits Colorado.(Note: This summary applies to the reengrossed version of this bill as introduced in the second house.)"
jurisdiction: "us/states/co"
legislature: "Colorado General Assembly"
session: "2018A"
identifier: "HB 18-1147"
citation: "Colorado HB 18-1147 (2018A)"
classification: ["bill"]
subjects: []
status: "enacted"
primary_sponsors: ["Don Coram", "Joann Ginal", "Kim Ransom"]
version_count: 8
action_count: 14
vote_count: 2
first_action: "2018-01-31T07:00:00+00:00"
last_action: "2018-04-26T06:00:00+00:00"
source: "openstates"
source_identifier: "ocd-bill/1104aad0-c2c5-45cc-a8e5-db3853b8717d"
source_url: "http://leg.colorado.gov/bills/hb18-1147"
source_hash: "d126df43910b4c040edc714b5b4ca074ceafc1ca946577fc3dc120149f91cc5b"
vintage: "2026-07-01"
source_snapshot: "https://data.openstates.org/daily/2026-07-01/public.pgdump"
retrieved_at: "2026-07-06"
confidence: "reported"
tags: ["legislation", "bill", "us-co"]
---

# Colorado HB 18-1147 (2018A) — Sunset Process Weather Modification

Sunset Process - House Health, Insurance, and Environment Committee. Sections 1 and 2 of the bill continue the regulation of people who modify the weather until 2033. Section 3 repeals a provision that prohibits weather modification that benefits another state if the other state prohibits weather modification that benefits Colorado.(Note: This summary applies to the reengrossed version of this bill as introduced in the second house.)

## Version chain

The bill's text revisions, in order — the diff chain from filing to enrollment.

1. **Committee Amendment** (committee substitute) — [source](http://leg.colorado.gov/sites/default/files/documents/2018a/bills/cr/2018a_hb1147_s_app_002.pdf)
2. **Engrossed (03/20/2018)** (committee substitute) — [source](http://leg.colorado.gov/sites/default/files/documents/2018A/bills/2018a_1147_eng.pdf)
3. **Final Act (04/19/2018)** (committee substitute) — [source](http://leg.colorado.gov/sites/default/files/documents/2018A/bills/2018a_1147_enr.pdf)
4. **Introduced (01/31/2018)** (committee substitute) — [source](http://leg.colorado.gov/sites/default/files/documents/2018A/bills/2018a_1147_01.pdf)
5. **Reengrossed (03/21/2018)** (committee substitute) — [source](http://leg.colorado.gov/sites/default/files/documents/2018A/bills/2018a_1147_ren.pdf)
6. **Rerevised (04/12/2018)** (committee substitute) — [source](http://leg.colorado.gov/sites/default/files/documents/2018A/bills/2018a_1147_rer.pdf)
7. **Revised (04/11/2018)** (committee substitute) — [source](http://leg.colorado.gov/sites/default/files/documents/2018A/bills/2018a_1147_rev.pdf)
8. **Signed Act (04/26/2018)** (committee substitute) — [source](http://leg.colorado.gov/sites/default/files/documents/2018A/bills/2018a_1147_signed.pdf)

## Votes

- BILL — **35–0** (pass) · upper
- BILL — **53–9** (pass) · upper

## Sponsors

- Don Coram — primary (person)
- Joann Ginal — primary (person)
- Kim Ransom — primary (person)

## Timeline

The legislative action history — every referral, reading, and vote.

- **2018-04-26T06:00:00+00:00** Governor Signed `executive-signature`
- **2018-04-19T06:00:00+00:00** Sent to the Governor `executive-receipt`
- **2018-04-19T06:00:00+00:00** Signed by the President of the Senate
- **2018-04-18T06:00:00+00:00** Signed by the Speaker of the House
- **2018-04-12T06:00:00+00:00** Senate Third Reading Passed - No Amendments `reading-3, passage`
- **2018-04-11T06:00:00+00:00** Senate Second Reading Special Order - Passed - No Amendments
- **2018-04-10T06:00:00+00:00** Senate Committee on Appropriations Refer Unamended - Consent Calendar to Senate Committee of the Whole `committee-passage`
- **2018-03-28T06:00:00+00:00** Senate Committee on Agriculture, Natural Resources, & Energy Refer Unamended to Appropriations `referral-committee`
- **2018-03-26T06:00:00+00:00** Introduced In Senate - Assigned to Agriculture, Natural Resources, & Energy `introduction`
- **2018-03-21T06:00:00+00:00** House Third Reading Passed - No Amendments `reading-3, passage`
- **2018-03-20T06:00:00+00:00** House Second Reading Passed - No Amendments `reading-2`
- **2018-03-16T06:00:00+00:00** House Committee on Appropriations Refer Unamended to House Committee of the Whole `referral-committee, committee-passage`
- **2018-02-22T07:00:00+00:00** House Committee on Health, Insurance, & Environment Refer Unamended to Appropriations `referral-committee`
- **2018-01-31T07:00:00+00:00** Introduced In House - Assigned to Health, Insurance, & Environment `introduction`

## Source

OpenStates / OpenCivicData bulk snapshot [2026-07-01](https://data.openstates.org/daily/2026-07-01/public.pgdump); origin `ocd-bill/1104aad0-c2c5-45cc-a8e5-db3853b8717d`. Confidence: reported (aggregated from official Colorado legislature records).