Rancho Mission Viejo

Rancho Mission Viejo, CA—Honor Award, Planning & Analysis


Steve Hohl
Water Concern, LTD.
Rancho Santa Margarita, CA



Rancho Mission Viejo is a large master planned community located between San Diego and Los Angeles nearly 10 miles east of the Pacific Ocean.

The Rancho Mission Viejo development consists of six Villages totaling 5,000 acres within the remaining 23,000-acre Ranch.  The community of Rancho Mission Viejo holds a unique and special character due to its multiple “Villages” each separated by thousands of acres of open space and “working” ranchlands.  There will be approximately 14,000 dwellings and 2,100 acres of landscape at build-out. Currently, there are two Villages complete – Sendero and Esencia.

The Developer/Owner, Tony Moiso, developed well established values regarding land ownership, management, and respect for its environment.  “Take care of the land and the land will take care of you…” has been a motto implemented by Tony on the Ranch whether on the cattle grazing lands, citrus or avocado farming operations, or within its community development division.



The project purpose was to plan and implement a turnkey irrigation program with the following stated goals and objectives:

  • Lead the effort to conserve water resources
  • Maximize efficiency of water procurement and delivery to provide adequate water to sustain a healthy landscape with a prescribed plant palette
  • Preparation of guidelines to promote and establish consistency of irrigation materials, design approach, and installation requirements
  • Master plan the water meter, controller, communications infrastructure, and weather station locations
  • Create and implement a water management program

An overall philosophy was created by the irrigation consultant which required bridging multiple disciplines.  That included soils, horticulture, engineering, landscape architecture, planning, installation contracting, maintenance, GIS, and property management.

The intent was to carry out the vision of water and resource management supported by the leadership of Rancho Mission Viejo to “take care of the land, so it will take care of you.”  Ultimately, there will be over 1,000 irrigation control timers, 30,000 control valves providing 5,990 acre feet of tertiary treated effluent to a diverse spectrum of plant materials and microclimates.



  • Helped develop plant palettes categorized for proper hydrozoning
  • Calculated peak water flow and volume demand for each parcel of land for hydraulic modeling
  • Hydraulic analysis to establish pressure zones
  • Developed a palette of irrigation materials to be used on the project
  • Established standards for GPS as-builts and GIS data for long term management
  • Developed design guidelines, specifications, and installation details
  • Lead the plan review process and site observation to help ensure implementation of the guidelines
  • Prepared a recycled water use guideline and exhibit for the water agency



The project required the collaboration with several disciplines, and the follow through over a large span of time to implement the initial vision required full team dedication.

The dynamics of irrigation rules, regulations and codes are continually modified to meet environmental and governmental influences.  Over the span of the initial phases of the community, guidelines were modified to meet or exceed these dynamics.

Future improvements in irrigation equipment and technology will continue to emerge and will need to be considered.



To view project images, click HERE