RMLUI Corner: Regulating for water conservation - water smart

by Elizabeth Garvin, AICP, Denver, Colorado

It has been a relatively wet summer in Denver, the local vegetation is about as green as it gets and there are not as many orange “Use Only What You Need” Denver Water lawn signs around, reminding us to not be wasteful. Colorado climate, though, is “best known for its low precipitation, aridity, and drought,”1 so this summer’s rain in no way guarantees that the flowers I plant and then ignore next summer will be nearly as lucky as the flowers I planted and then ignored this year. Water, or the lack thereof, is always the subject of planning conversation in the West. And as our population in this part of the country continues to grow – we are the light green 35.8 percent in the growth percentage chart to the right – it appears that many of our communities, large and small, will need to find more creative and efficient methods to make the water we have – annual rankings provided in the table to the right – go much further. In this article, we are going to explore the range of local regulations available to encourage and require water conservation.

A. Planning for Water Conservation

The highest rates of per-capita water usage in the United States occur in the dry Western states, with more than half of our household use going to water lawns and gardens.2 In many Western communities, though, the comprehensive plan does not specifically address water supply or conservation and the only place local zoning and subdivision regulations consider water is in the requirement that the applicant “prove” the availability of adequate water for a new development. Water planning seems to have fallen between the local jurisdictional cracks of home rule, community planning, public works, emergency preparedness, and regional government, not to mention the challenges of coordination between private water providers and local government.3 There are states that require local water planning and local governments that have undertaken voluntary water planning,4 but for other communities there can be gaps in the planning information and process. Good plans support the best regulations, so the first recommendation of this column is to consider water supply and conservation planning as part of the overall land use planning and development process.

B. Applying Water Law

Before describing the various approaches municipal governments have available to regulate for water conservation, it is important to add a note to the reader that water law, not just land use law, may govern any number of aspects of a community’s conservation regulatory process. For example, even though the use of rain water harvesting for plant irrigation has been practiced since the beginning of human agriculture, it was illegal until 2009 to capture and reuse rainwater in Colorado because that water had already been legally appropriated to a specific water user, who was typically not the homeowner.5 And while Colorado changed the law, other states have not. Therefore, it is important to have local regulations reviewed in light of the water law of your jurisdiction in order to understand the impacts of the proposed regulations on the existing rights of water users.6

C. Pricing Water and Financing Water Systems

As with most land use issues, there is both a regulatory approach and a funding aspect to water conservation. According to the U.S. Environmental Protection Agency,7 there are multiple gaps and oversights in the water provision and pricing system that inadvertently lead to excess water use and waste. These include water providers:

  1. Choosing to defer maintenance on existing, leaking pipes in order to conserve funds to extend the system to new development;
  2. Not pricing water service to reflect transmission costs to large-lot, dispersed development; and
  3. Failing to recognize that water systems in low-density areas that are longer and require higher pressure to operate leak more than systems serving higher-density development.

If the water system in your community is publicly-owned and operated, it may be worth considering the sum of the actual long-term costs to supply low-density residential development and reflect those costs through the pricing system. Some communities take this approach one step further and establish conservation pricing that increases water rates at peak use times. A study by four Florida water management districts found that “[w]ater use decreases with increases in water price. The decreases are predictable and statistically valid.”8 The study also found that users in the most expensive homes both used the most water and were able to reduce that use at a greater rate than other homeowners because they used water for more discretionary purposes, such as landscape irrigation.

D. Water Conservation-Oriented Regulation

Local regulation for water conservation can take place at both a community-wide level and an individual site-level. In the zoning and subdivision regulations, communities can both exercise direct control and establish development incentives to encourage water conservation.

1. Require and Provide Incentives for Smaller Lots

Research shows that residential developments on smaller lots use less water, or conversely, large lot residential development results in greater water use.9 In Utah, as lot size decreased from 0.5 to 0.2 acres (22,000 sq. ft. to 9,000 sq. ft.), per capita water demand reduced from 210 to 110 gallons per day, a roughly 50 percent difference.10 Similarly, in Seattle, households on .15 acre lots (6,500 sq. ft.) use 60 percent less water than those on .37 acre lots (16,000 sq. ft.).11 This lines-up with the finding in the Bridging the Gap report12 that much of our household water use goes to irrigation. Most current studies on land use and water conservation identify reduction in lot size as one of the most effective means a community can use to directly conserve water.

In most communities, the minimum lot size for development is governed by the zoning regulations. In a growing number of communities, the zone district also specifies a maximum lot size for the district, such as those required by Palo Alto, California in the chart to the right. Smaller lot sizes can be achieved through a number of approaches, including:

  • Reducing the minimum lot size in existing districts;
  • Creating a small-lot zoning designation that permits the development of a range of housing types appropriate to small lots, such as single-family detached, single-family attached, rowhouse/townhouse, and apartment uses and establishes reduced set-backs proportionate to the lot size;
  • Establishing an infill-lot process that allows the creation of small-lot infill development where appropriate;
  • Creating a small-lot overlay that permits the resubdivision of lots in appropriate larger-lot zone districts;
  • Establishing cluster development subdivision standards; and
  • Permitting mixed-use and second-story and higher residential development over commercial development.

When the community has appropriate small lot zoning in place, local officials may also consider incentives to encourage the use of that district/zoning option. This might include a density or square foot bonus for small lot development, water or impact fee reductions or waivers, or expedited plan and permit approval. The adoption of small lot development standards may also be necessary to encourage the quality of design the community would like to see in these development areas.

2. Establish Water Conservation Policies and Standards

Most modern zoning regulations include any number of development standards designed to address specific development requirements such as parking, lighting, and building design. Water conservation standards can be both added to this list as a specific group of regulations, and incorporated throughout the other standards. Landscaping and open space standards are two areas that can typically be revised to better encourage water conservation. Turf grass is the current poster child for water-driven change. According to planning lore, turf grass moved across the country with our formerly-British ancestors who somehow failed to realize that they had moved from a rainy island to a vast and weather-diverse continent. Rolling turf grass lawns maintained their status and appeal regardless of where we built our homes. And while Kentucky Bluegrass is stunning in Kentucky, it may not be the best ground cover in Montana.

There are multiple examples of zoning codes across the West that specifically limit the amount of turf grass used on site to a relatively small percentage of the site, as well as communities that have sponsored turf-grass buy-back programs.13 Additional topics that can be addressed through water conservation regulations include:

  • Use of native and drought-tolerant plant materials and non-plant groundcovers in landscaping and open spaces/existing landscape conversion to more water-wise materials;
  • Type and design of irrigation systems along with timing of use and restrictions on water waste;
  • Availability and use of greywater systems;14
  • Rainwater harvesting; and
  • Reduced use of impervious surfaces/replacement with pervious materials.

While making water-specific changes to the land development regulations, staff should also consider changes to related regulations that may be necessary, such as permitting water collection systems in side-yard setbacks, changing required materials standards for driveways and parking areas, and prohibiting private development covenants from restricting water conservation measures.

3. Require PUD and Master-Planned Communities to Design for Water Conservation

Planned unit development (PUD or PD) and master-planned communities are designed and submitted for development approval as complete development. Most local governments look carefully at the street layout, open space provisions, and mix of housing styles. Local governments can also review the development applications for water conservation design, preferably through a specific water conservation review requirement included in the PUD approval criteria such as this requirement from Cochise County, Arizona’s Rezoning Evaluation Factors:

12. Water Conservation. Uses proposed with the rezoning involving Master Development Plans shall show compliance with the water conservation policies of Section 102E in the Comprehensive Plan and the approved Master Development Plan.15

A number of large master-planned developments have been approved in the past ten or fifteen years that include water conservation design, including the Stapleton neighborhood in Denver, Colorado; Sterling Ranch in Douglas County, Colorado,16 Civano, in Tucson, Arizona; and Rancho Viejo and Oshara Village in Santa Fe, New Mexico.17

4. Home Design and Use

There are also numerous changes that can be made both to home design and to occupant use that can conserve water through more efficient use. These changes are typically governed by local building codes and educational programs and are beyond the scope of this article. More information is available through U.S. EPA’s WaterSense program.18

Elizabeth Garvin, AICP, is an attorney with Spencer Fane Britte & Browne. She serves on the Regional Board for the Rocky Mountain Land Use Institute.


  1. Thanks to the USGS for pointing that out. Mark T. Anderson and Lloyd H. Woosley, Jr., Water Availability for the Western United States – Key Scientific Challenges, U.S. Geological Survey Circular 1261 (2005).
  2. Bridging the Governance Gap, Strategies to Integrate Water and Land Use Planning, The University of Montana Center for Natural Resources and Environmental Policy, Policy Report No. 7, pg. 6 (2010)(“Bridging the Governance Gap”).
  3. For a much more detailed discuss of the disconnect between water and land use planning, see Bridging the Governance Gap.
  4. Such as Minnesota, Washington, North Carolina, California, Virginia, and Florida.
  5. Kirk Johnson, It’s Now Legal to Catch a Raindrop in Colorado, New York Times (June 28, 2009) (http://www.nytimes.com/2009/06/29/us/29rain.html?_r=0)
  6. We will cover takings law in another column. Your community does not want to be a poster child for water law takings through conservation regulations.
  7. Growing Toward More Efficient Water Use: Linking Development, Infrastructure, and Drinking Water Policies (2006).
  8. Southwest Florida Water Management District, Water Rates: Conserving Water and Protecting Revenues (http://www.swfwmd.state.fl.us/conservation/waterrates/).
  9. Western Resource Advocates, New House New Paradigm, A Model for How to Plan, Build, and Live Water-Smart, pg.4 (2009) (www.westernresourceadvocates.org) (“New House New Paradigm”).
  10. Id, citing U.S. EPA, Growing Toward More Efficient Water Use.
  11. See note 10.
  12. See note 2.
  13. Such as the Santa Monica, California Office of Sustainability and the Environment: http://www.smgov.net/Departments/OSE/Rebates/Cash_for_Grass_Rebate.aspx.
  14. “Greywater comes from washing machines, bathrooms sinks, and showers, while “dark greywater” from dishwashers or kitchen sinks might also be included. In contrast, wastewater from toilets and urinals is called blackwater. In residential buildings, the majority of water (between 50% and 80%) falls into the greywater category and can be collected for reuse.” Green Building Alliance, Greywater Systems (https://www.go-gba.org/resources/green-building-methods/greywater-system/_
  15. https://www.cochise.az.gov/sites/default/files/planning_and_zoning/Rezoning%20application%20new.pdf
  16. For disclosure purposes, Sterling Ranch is represented by an attorney who practices in my law firm.
  17. New House New Paradigm at ii.
  18. http://www.epa.gov/watersense/about_us/what_is_ws.html

Published in the October/November 2014 Issue

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