Harvest the Water-Saving Potential in Your Yard

• Water runs off my property towards the street.
• My yard absorbs water.
• Water runs from the street into my yard.

New Development | Slow that Runoff

Features: Basins | Berms | Bioswales | Rain Chain | French Drain

This yard design is ideal for sloped yards that have a steeper grade than normal. Sometimes these homes are found near mountains such as South Mountain or Camelback Mountain. The home is modeled for newer styles of homes commonly found in the Phoenix Metro Area. The features included in this design are intended to slow the movement of rainwater:

• Permeable, decomposed granite pathways
• A series of basins with a rock check dam system
• Gutters with downspouts to direct water off of your roof and into your basin
• A rain chain
• A French drain under the driveway to move water to the other side of the yard

1. Basin: A stormwater harvesting basin, also known as a rain garden, is a specially designed area that collects and temporarily stores rainwater. These basins typically have sloped sides that create a depressed area that collects stormwater runoff, allows it to infiltrate the soil, and supports native vegetation.
2. Berm: A raised area located just downslope of an existing basin (Lancaster, 2019).
3. Bioswale: A bioswale is a linear channel designed to collect and store stormwater, allowing it to infiltrate the ground. Bioswales are typically filled with plants that help remove pollutants from the water, thereby preventing those pollutants from infiltrating in the ground or entering a natural water body. They are commonly used in urban areas to reduce localized flooding, improve water quality, and create a more sustainable landscape.
4. Rock Check Dam (Sediment Trap): A sediment trap is a feature designed to capture sediment and other debris before stormwater runoff enters a GSI feature, like a bioswale. A sediment trap can either be a concrete flat pad or an earthen berm placed at a curb opening, at least 2” lower than the curb opening level. By capturing sediment, the trap helps to reduce the amount of pollutants that would otherwise be carried by stormwater into your bioswale. This helps protect water quality, promote plant health, and prevent the accumulation of sediment.
5. Rain Chain: See item 7.
6. French Drain (Permeable Hardscape): Permeable hardscape refers to hard surfaces that are either porous or designed with void spaces that allow water to infiltrate (pass through) the material and soak into the ground. Examples include permeable pavers, gravel or crushed stone pathways, and open-grid pavement systems.
7. & 8. Downspout & Gutter: A rain gutter system, also known as a guttering system or simply gutters, is a network of channels or troughs that collect and redirect rainwater from the roof of your home or garage. It can then be captured into a rain barrel or directed to a stormwater harvesting basin. This prevents water from flowing directly off the roof, causing damage to building foundations, hardscape areas, or landscape.

Definitions can be found in:

• City of Phoenix. (2024). Green Stormwater Infrastructure Handbook for Residents.  https://www.phoenix.gov/pddsite/Documents/Phoenix%20Green%20Infrastructure%20Handbook%20for%20Residents%20Oct%202024.pdf 
• Lancaster, B. (2019). Rainwater Harvesting for Drylands and Beyond, Volume 1: Guiding Principles to Welcome Rain Into Your Life and Landscape (Vol. 1). Rainsource Press.

Historic Homes| Naturally Good at Absorption

Features: Agave Terraces | Basins | Permeable Paver Patio

The rainwater features included in this design are basins, a permeable paver patio, and a series of berms positioned like agave terraces. This example offers ideas about how to create spaces for relaxing and socializing in your yard. This yard and house are based on historic homes abundant within central Phoenix.

Ranch Style | Protective

Features: Basins | Berms | Bioswales | Permeable Driveway

This yard design would be most ideal for residents who live near floodplains, have converted a yard that was previously flood-irrigated, or are situated in depressed areas adjacent to natural waterways. The features included in this design can help to mitigate stormwater entering the yard.

• A series of basins
• A protective berm
• A bioswale
• A permeable driveway
• Gutters with downspouts

The design of the yard invites you to create a space to gather by providing natural shade over open areas. This design aims to show the often-underutilized “front yards” are outdoor areas that can be a great place to gather. The home was modeled after ranch-style homes that were popular after the mid-century and are commonly found in Phoenix.

This project is a collaboration between Arizona State University Project Cities, The Design School, and the City of Phoenix Water Services Department. The project’s goal is to provide introductory educational material that focuses on methods to easily save water outdoors. The team gathered feedback from Phoenix residents, subject matter experts, and Homeowners Associations to ensure that many perspectives and priorities were included in the designs. Phoenix residents can find inspiration to bring rainwater harvesting into their front yards. The designs also include native, drought tolerant plants. This Storymap and these designs are the beginning of a conversation about passive rainwater harvesting in Phoenix, and our team hopes that you find a spark of inspiration to include in your xeriscape vision board.

The project contains three different and adaptable passive rainwater harvesting designs. Each design has a few different features and can suit a yard of any size – just customize!

The Arizona State University Project Cities program uses an innovative approach to traditional university-community partnerships. Project Cities connects community partners facing sustainability challenges to faculty experts teaching courses at ASU to develop solutions through project-based learning with undergraduate and graduate students. This is a win-win partnership, which allows students to reinforce classroom learning and practice professional skills in a real-world client-based project. Project Cities is a member of Educational Partnerships for Innovation in Communities Network (EPIC-N), a growing coalition of more than 60 educational institutions partnering with local government agencies across the United States and around the world.

This project is a culmination of student research and design efforts as part of an undergraduate independent study course and honors thesis completed from spring 2023 through spring 2024 in The Design School. These efforts were supported through Project Cities in partnership with the City of Phoenix Water Services Department.

As the fifth largest city in the United States and one of the most populous desert cities in the world, Phoenix thrives because of water resource planning and conservation. History has shown that people on this land will flourish when they are mindful of their water use.

The City of Phoenix strives to empower its residents to save water their way. The Conservation Team focuses on community action, resilience, and engagement, and aims to increase access to water-saving solutions by providing instructional resources and assistance. Our desert home is experiencing changes, and Phoenix welcomes new residents daily. When joining our city, we welcome you to embrace the Desert Ethic and use water efficiently and responsibly, always! When we all live with water in mind, we find a deeper connection to the place that we call home and create a connection to share: the Culture of Conservation. In collaboration with our residents, the Phoenix Water Services Department is committed to responsible stewardship of our water, infrastructure, and environment. Conservation is a community phenomenon, and a resilient Phoenix requires your participation.

Yes, there is water in our desert. But we should never take it for granted.

In ten years, we hope to see a City that has risen above its challenges and overcome the threat of water shortages. Our dedication to creating a resilient Phoenix requires water, and the Water Services Department works daily to deliver on its promise: to provide clean, safe, and reliable drinking water and wastewater services. New water sources are hard to find in the desert, but technology has given us a new way to adapt. Advanced Water Purification projects will close the loop in our urban water cycle and help our community to be more efficient than ever. But, resilient actions are not limited to what happens in government. Resilient futures start in the heart of the community, with you: in your yard with your grandchild; at your mailbox with a neighbor; at the kitchen table with a friend. Conversations and actions, undertaken together, create the culture of conservation that we need to stay connected to our desert home. When we care for the place that we live in, we find greater satisfaction. When we learn to see ourselves as a part of the water cycle, we can understand the role that we play in immediate environmental sustainability and long-term resilience for the future of Phoenix.

Our resources are designed to complement the work that has already been done by local change-making organizations. The Arizona Municipal Water Users Association (AMWUA), Water – Use It Wisely (WUIW), and the Watershed Management Group (WMG) have literally written the book(s) on how to save water. Our Storymap is the result of an initial conversation with our community that explains how the existing resources can be used to do more to conserve. Together, resources on proper irrigation, yard design, rainwater harvesting, native plant selection, and more, offer all of the instructions that residents could need to make efficient and responsible water use a commitment. The primary goal of the collaboration between ASU Project Cities, The Design School, and Phoenix Water Services was to create a comprehensive, easy-to-use resource to help residents determine how they can reduce water consumption through xeriscaping, native plant use, and rainwater harvesting.

In order to include critical stakeholder perspectives, a multifaceted approach was designed to increase public participation in the crafting of solutions. Surveys included an exploration into how residents could modify their outdoor spaces without needing permits or professional assistance, aiming to make water-saving projects a possibility for residents who might not be able to afford the additional costs of working with landscape professionals. If residents would be willing to trade bespoke customizations to save money, our designs could give the inspiration that they need to grab their shovels, and the body of literature online from experts like the Watershed Management Group and AMWUA could help them to find the information and instructions that they would need to complete their projects. Additionally, this collaboration aimed to understand resident preferences, identify barriers to adopting sustainable practices, and analyze how rainwater appears in various neighborhoods across Phoenix. Lastly, the research aimed to curate accessible, practical information to help residents reduce outdoor water consumption and integrate these insights into future resources.

Residential Survey

The project purpose was informed by existing literature and new surveys. For example, a 2018 survey by the American Society of Landscape Architects (ASLA) identified strong demand for sustainable residential landscape features such as native plants, drought-tolerant species, low-maintenance landscapes, permeable paving, drip irrigation, and rain gardens. Additionally, ASLA found that much of the residential landscape architecture market serves higher-income households, which creates a cost-restrictive limitation, reducing participation.

Expert Interviews

The final designs were informed by the perspective of ten municipal landscape and water management professionals. The team conducted multiple interviews, and four consistent challenges were identified. In order to make our project successful, the resources to be created would need to address plant availability, variations in urban hydrology, resident perceptions, and community engagement.

Homeowner Associations (HOAs) enforce various rules and regulations through bylaws and CC&Rs: Covenants, Conditions, and Restrictions. These rules are unique to the individual community, and thus are not always similar throughout the City. They often outline the associations' and homeowners' obligations and rights in terms of shared landscapes, front yards, and design choices. Given the estimate that HOAs had influence over approximately 50% of Phoenix residences, it was crucial to identify potential barriers to yard conversions within these communities. The City of Phoenix’s Water Services Department helped facilitate this process by reaching out to 76 participating HOAs, of which only six provided the requested documents for analysis, highlighting the challenge of accessing this information among over 1,700 HOAs in the city.

Approximately 220 survey responses were received in total by January 31st, 2024. The majority (86%) of participants lived in Phoenix year-round while only around 2% lived in Phoenix seasonally. Out of the 220 responses, 132 participants included their zip code. From those 132 participants, most responses were from 85006, 85022, and 85254 (Primarily Central Phoenix).

• The majority of respondents were born in the mid-1970s
• 72% were not born in Arizona
• 90% lived in a typical, residential single family home
• 86% said they could change their landscape in their home
  • A measurement of landscape maintenance autonomy
  • 80% of participants lived in an HOA
• 65% used a drip irrigation/sprinkler system and 45% used hand watering technology (hose/watering can)

The following four survey questions provided key information to shape the rainwater harvesting yard designs:

1. What happens to your yard during a rain event?
2. Would you like to see wildlife in your area?
3. How do you use your front yard?
4. If you had a choice, which would you choose to reduce the amount of water you use outdoors?

Based on residential survey responses, three main types of rainwater behavior were identified. Water in Phoenix yards may rapidly exit a yard, cause flooding, or be absorbed by the existing soil during rain events. Visualizing these trends spatially by zip code shaped the approach to the rainwater harvesting design. Three plans were proposed based on rainwater behavior to maximize water usefulness during a rain event.

The majority of responses were highly in favor of seeing wildlife. The types of wildlife sightings most desired by residents included pollinators such as bees, hummingbirds, and butterflies.

The majority of responses indicated infrequent use of “front yard” spaces.

When residents were provided multiple options for what they would choose to do to reduce the water they use outdoors, the majority of respondents were in favor of adding rainwater harvesting features.

Passive rainwater harvesting, xeriscaping, and the use of native and desert-adapted plants can empower residents to reduce outdoor water consumption while maintaining drought-resilient yards. With increased public interest and desire for water conservation, developing user-friendly guides for residents can drive sustainable change in local communities. 

The proposed designs offer new ideas for how Phoenix residents can incorporate passive rainwater harvesting features while also providing habitat for pollinators and maximizing front yard space.

This project is a collaborative effort between the Arizona State University Project Cities program, The Design School at ASU, and the City of Phoenix Water Services Department. ASU Project Cities and City of Phoenix extend their gratitude to Sofia Lomeli for her invaluable contributions to this effort throughout her Honors Independent Study and Honors Thesis coursework as part of her Bachelor of Science of Landscape Architecture degree program, under the guidance of Dr. Paul Coseo and Dr. Chingwen Cheng.

Lomeli's Spring 2024 Honors Thesis Defense is available for viewing: