WELS - Water Efficient Landscaping Standards

An 18-month pilot phase began June 22, 2017 after adoption of Ordinance 16, Series 2017 and ended on December 31, 2018. For all permit applications accepted by the City during the pilot phase, all documentation described in this document was required, and irrigation and landscaping installation requirements needed to be met. During the pilot phase, the City encouraged applicants to meet the 7.5 gallons/season/square-foot water budget, however, failure to meet the Maximum Applied Water Budget during the 18-month pilot phase did not hold up applicant’s building permit and/or certificate of occupancy. Effective January 1, 2019, full compliance with the City of Aspen Water Efficient Landscaping Ordinance and Standards will be required.

WHY does the City of Aspen have Water Efficient Landscaping Standards (WELS)?  

  • To reduce outdoor water demand – 60-70% of Aspen’s treated water is sold for outdoor use. 
  • To promote the values and benefits of healthy landscapes while using water as efficiently as possible. 
  • To establish a structure for planning, designing, installing, maintaining, and managing water-efficient landscapes.
  • To use water efficiently without waste by setting a Maximum Water Budget for water use and reduce water use to the lowest practical amount.

To learn more, please read our 2025 Water Efficient Landscaping Standards (PDF).

WHEN is a WELS review needed? 

A WELS Review is generated from the Master Building Permit submission when 1 of the following apply: 

  • The disturbance area of the build or addition is over 1000 square feet AND greater than 25% of the entire lot. 
  • Permit applications with more than ten thousand (10,000) square feet of affected area.
  • All permit applications with internal work that demolishes greater than 50% of the existing structure.

If you aren’t sure if you will be triggered for a WELS review, send a Pre-Submission Checklist (PDF) to the WELS Plans Reviewer (megan.killer@aspen.gov | 970-429-1975) 

WHAT do I need to submit? 

WELS Application Package 

Inspection Requirements (to be submitted before an inspection can be scheduled) 


Upload Your Application Package

To upload your WELS application package, please use the City Permit Portal (Salesforce).


Contact:

Megan Killer – WELS Plans Reviewer

City of Aspen Utilities Department

megan.killer@aspen.gov

Phone: 970-429-1975

Nonfunctional Turf Ban

EffTurf Alternative Exampleective January 1st, 2026, Colorado state bill SB5 will ban the planting of “nonfunctional turf” and “nonfunctional artificial turf” in certain circumstances.

Nonfunctional turf/artificial turf is defined as non-native or non-climate adaptive turf grass species that are planted in areas that are only for aesthetics and do not have any other designated purpose or use, such as a sports field, dog play areas, etc.

Nonfunctional turf/artificial turf will not be allowed to be planted on commercial properties, common interest areas or public right-of-way landscaping for new builds or redevelopment that must comply with WELS. See section 4.3.2f in the Water Efficient Landscaping Standards for more information.

Please see the following resources for plant suggestions and native grass alternatives to non-native turfgrasses!

  1. General Information and Documents
  2. County Process
  3. Find an Auditor and Training Opportunities

General Information & Documents

  1. WELS Pre-Submission Checklist (PDF)
  2. WELS - Water Efficient Landscaping Standards January 2026 (PDF)
  3. WELS Documentation Requirements List (pdf)
  4. ECU Calculator/WELS Water Budget Worksheet - Residential 2026 (.xslx)
  5. ECU Calculator/WELS Water Budget Worksheet - Commercial 2026 (.xlsx)
  6. WELS Irrigation Audit Report Effective June 1st, 2025 (PDF)
  7. Irrigation Audit Approval Letter (WELS after 1.1.19)
  8. WELS Example Plans (PDF)

Resources                                                                                           

  1. Division of Water Resources Rainwater Collection Information Table (PDF)
  2. Turfgrass Species Selection Guidelines by CSU Extensions
  3. Fire Resistant Landscapes by CSU Extensions