Changes to the Water Petal (Q1 24)

May 2024
Corrections made as needed throughout for grammar, punctuation, nomenclature, typos, and links.

I05 Responsible Water Use (C3)

CLARIFICATIONS

• Potable Water Reduction Clarifications
  • Creating the Baseline
    • Re-organized for clarity of meaning and extensive detail added about developing customized baselines.

• Irrigation Clarifications
  • Interior Landscapes
    • Guidance added regarding potable water and watering interior plants.

• Stormwater Clarifications
  • Re-organization throughout for clarity of meaning.
  • Downstream Context
    • New clarification added with definitions of downstream contexts referred to in Table 5-6.
  • General Stormwater Requirements
    • Historic and Pre-development Hydrology
      • Subheading changed to reflect clarified definition of “historic hydrology” and intent that for purposes of the Imperative, “historic hydrology” and “pre-development hydrology” have the same meaning.
  • Modeling
    • Detail provided on the required modeling outputs.
  • Municipal Stormwater Connection
    • Clarification making explicit that the subject flows are those leaving the site in compliance with the thresholds specified in Table 5-6.

EXCEPTIONS

• AMENDED
  • WT-001 Site-Constrained Stormwater Discharge
    • Specificity added regarding analyses, documentation, and calculations required for use of the exception and clarification that flows off site must not exceed historic volumes.

CALCULATIONS

• Example Customized Baseline By Standard End Use
  • New example calculation

DOCUMENTATION REQUIREMENTS

• I05-1 Potable Water Use Documentation
  • Ready Audit
    • Additional documentation required regarding assumptions and calculations for all projects and additional detail on what must be provided when using a customized baseline.

• I05-2 Irrigation Documentation
  • Ready Audit
    • Added detail regarding what must be shown on landscape drawings.

• I05-3 Stormwater Documentation
  • Ready Audit
    • Added detail regarding documentation to show compliance with Peak Runoff Rate and Volume Management Control requirements.
  • Final Audit
    • If connecting to a municipal stormwater system:
      • Required documentation reduced; metering requirement removed and calculations of pumping energy moved to I07.

RESOURCES

• Resources added to support climate adaptation calculations
  

I06 Net Positive Water

CLARIFICATIONS
*Acceptable Supply

• Groundwater
  • New subheading to highlight additional detail added regarding analyses needed to show that the rate of withdrawal does not exceed the groundwater recharge rate.

EXCEPTIONS

• AMENDED
  • WT-008 Scale Jumping Within An Aquifer
    • New requirement to request approval in advance for use of the exception added along with description of supporting documentation that must accompany the request.

DOCUMENTATION REQUIREMENTS

• I06 Water Narrative
  • Ready Audit
    • Detail regarding analyses required for projects using groundwater consistent with the language added to the Acceptable Supply clarification in this update.
    • Detail added regarding what is needed to demonstrate resiliency requirements.

• I06-3 Metered Data Table
  • Final Audit
    • Projects Using a Well
      • Additional calculation confirming that withdrawal has not exceeded the recharge rate cited in the Ready Audit documentation.