Exceptions

All Exceptions require additional documentation. See I05 Exception Documentation Summary Table.

WT-001 Site-Constrained Stormwater Discharge

Use of this exception requires ILFI approval in advance; see details below.

Building projects that are unable to meet the stormwater volume management requirements of Table 5-6 due to site constraints (e.g., zero-lot-line buildings, sites in high-density areas, or those with geologic or soil constraints) are permitted to discharge stormwater volumes off site in excess of the limits specified in Table 5-6, but no greater than historic discharge volumes, after having optimized stormwater management on site per the requirements cited below. All other stormwater requirements, including the peak discharge rates specified in Table 5-6 and treatment requirements specified in Table 5-7, remain in effect.

The project must provide:

• Calculations showing that the discharged quantities do not exceed historic runoff volumes from the site; and
• A narrative explaining the optimized strategy in light of site-based opportunities and limitations in each of these categories:
  • Evaporation/Evapotranspiration: Show that all areas for water uptake by plants or other strategies have been fully utilized (e.g., living walls, green roof, vegetation, cooling tower make-up, irrigation for urban agriculture, etc.);
  • Infiltration: Show that infiltration strategies have been investigated and utilized;
  • Beneficial Reuse: Show that the feasibility of beneficial reuse of the stormwater has been analyzed for at least toilet/urinal flushing, laundry, irrigation, and other non-potable uses specific to the project and utilized where feasible; and
  • Ecological Benefit: Demonstrate any positive ecological benefits that result from stormwater leaving the site (e.g., nutrient assimilation, recharge of riparian or subsurface zones, etc.).
    Where stormwater drains to a combined sewer system, on-site detention must also be implemented to the maximum practical extent.

Use of this exception requires submitting the optimized stormwater strategy narrative specified above, as well as all other analyses identified in the Stormwater Clarifications of this Imperative, for preapproval by ILFI via a Request for Ruling.

WT-002 Non-Potable Water for Uses Other Than Irrigation

Project teams located in jurisdictions that either prohibit non-potable water for irrigation or require higher levels of treatment for irrigation than interior non-potable demands may use potable water for irrigation and instead use non-potable water to offset potable interior demands, provided that they show interior non-potable demands (e.g., process water, toilet flushing, or laundry) equal or exceed that of irrigation demands.

To use this Exception, project teams must still use a baseline that excludes irrigation and must still meet the potable water reduction requirements.

WT-011 Turf in Affordable Housing Projects

Use of this exception requires ILFI approval in advance; see details below.

Affordable housing projects that can demonstrate a funding requirement or clear programmatic need for use of turf that requires irrigation in their climate may use potable water to irrigate the turf only, subject to the performance and documentation requirements listed below.

Use of this exception requires approval in advance. To request approval, project teams must submit a Request for Ruling providing a narrative that justifies both the use of turf on site and the proposed areal extent and that details the Handprinting strategy.

Performance requirements:

• 100% of potable water used for turf irrigation during the performance period must be Handprinted;
• The area of turf must be the smallest amount that will meet the programmatic need;
• A water budget for irrigation must be established using the EPA Water Budget Tool, specifying low-water turf as the only plant type, and the installed irrigation system must be appropriate to achieving the maximum percentage reduction identified by the tool;
• The irrigation system serving the turf must be sub-metered; and
• The area dedicated to turf (as well as the associated soil preparation, species chosen, watering regime, and maintenance plan) must be factored into development and implementation of the Adaptive Plan required under Ecology of Place. Use of this Exception does not remove or affect the requirements of the Ecology of Place Imperative.

Documentation requirements:

• Narrative identifying the programmatic or funding requirement and justifying the quantity of turf area, including identification of the nearest public turf access (playground, park, etc.) and explanation of why the public option cannot meet program requirements.
• Baseline and reduction calculations using the EPA Water Budget Tool (calculation to include turf areas only and must use low-water turf variety). The area of turf must be equal in both the baseline and reduction calculations and must match the turf area called out on the project’s landscape drawings.
• Project contract documents showing a turf planting plan (including soil prep and depth, seed/sod type, planting schedule, and establishment irrigation requirements) showing alignment with best practices/research for low-water turf establishment and survival.
• Operation and maintenance (O&M) manual including a turf maintenance plan (irrigation schedule, mowing schedule/minimum turf height, and recommended soil amendments) showing alignment with best practices/research for low-water turf establishment and survival.
• Sub-meter data showing potable water used for irrigation.
• Handprinting strategy, including specific beneficiary site and methods for establishing baseline and savings achieved, demonstration of implementation and data showing that potable water savings equaled at least the quantity of water used for turf irrigation at the project site over the performance period.
• Data showing compliance with all other measuring and calculation requirements specified under the Water Handprinting for Affordable Housing Clarifications in I05 – Responsible Water Use, including calculations showing water savings will remain for 15 years.

WT-012 Turf for Public and Nonprofit Landscape + Infrastructure Projects

Public and nonprofit projects that can demonstrate a clear programmatic need for use of turf that requires irrigation in their climate may use potable water to irrigate the turf only, subject to the performance, advocacy, and documentation requirements listed below. Eligibility for this exception requires the site to allow free public access. In addition, use of this exception requires advocacy to local or regional water regulating authorities for the development of non-potable irrigation infrastructure, per the advocacy requirements section below.

Performance requirements:

• 100% of potable water used for turf irrigation during the performance period must be Handprinted.
• The area of turf must be the smallest amount that will meet the programmatic need.
• Low-water turf must be specified. The water budget for irrigation must be established using the EPA Water Budget Tool selecting for low-water turf. The installed irrigation system must be appropriate to achieving the maximum percentage reduction identified by the tool.
• The irrigation system serving the turf must be sub-metered.
• The area dedicated to turf (as well as the associated soil preparation, species chosen, watering regime, and maintenance plan) must be factored into development and implementation of the Adaptive Plan required under Ecology of Place. Use of this Exception does not remove or affect the requirements of the Ecology of Place Imperative.
  

Advocacy requirements:

Project teams must research and advocate to local or regional water regulating authorities for the development of non-potable irrigation infrastructure per the following:

• Conduct research into the systems and requirements of a minimum of two other municipalities that provide reclaimed water systems.
• Send letters to a minimum of three representatives from the Authority Having Jurisdiction (AHJ) describing the project and certification requirements, why there is a need for non-potable water for irrigation, and case study examples from other municipalities.
• Hold at least one meeting with relevant representatives of the AHJ to discuss letter content and potential paths for future non-potable water resources.
• Advocacy must be directed to departments in a position to make decisions and implement changes to water policy or water development and can include but are not limited to:
  • Planning department
  • Department of Health
  • Water and/or sewer utility
  • City council
  • Office or department of sustainability or environment
  • Regional water districts

Documentation requirements:

• Narrative identifying the following:
  • Programmatic need for turf;
  • Justification for the quantity of turf area;
  • Non-potable irrigation strategies explored; and
  • Justification of irrigation needs based on monthly rainfall and specific turf irrigation requirements.
• Documentation of advocacy for local or regional non-potable irrigation supply, including copies of letters sent and meeting minutes (see Advocacy Requirements).
• Documentation showing the project is accessible to the public and does not require entry or membership fees.
• Baseline and reduction calculations using the EPA water budget tool (calculation to include turf areas only and must use low-water turf variety). The area of turf must be equal in both the baseline and reduction calculations and must match the turf area called out on the project’s landscape drawings.
• Project contract documents showing a turf planting plan (including soil prep and depth, seed/sod type, planting schedule, and establishment irrigation requirements) showing alignment with best practices/research for low-water turf establishment and survival.
• Operation and maintenance (O&M) manual, including a turf maintenance plan (irrigation schedule, mowing schedule/minimum turf height, recommended soil amendments) showing alignment with best practices/research for low-water turf establishment and survival.
• Sub-meter data showing potable water used for irrigation.
• Handprinting
  • Handprinting strategy, including specific beneficiary site and methods for establishing baseline and savings achieved, with demonstration of implementation and data showing that potable water savings equaled at least the quantity of water used for turf irrigation at the project site over the performance period.
  • Data showing compliance with all other measuring and calculation requirements specified under the Water Handprinting for Affordable Housing Clarifications, including calculations showing water savings will remain for 15 years.