IRWD — An Overview

AN OVERVIEW

IRWD AT A GLANCE 181 square miles SIZE OF DISTRICT

Irvine Ranch Water District is an independent special district that provides high-quality drinking water, reliable sewage collection and treatment, drought-proof recycled water and environmentally sound urban runoff treatment for central Orange County. The Board of Directors is responsible for the District’s policies and decision-making. The General Manager and District staff supervise day-to-day operations. STEWARDS OF WATER EFFICIENCY IRWD water comes from local groundwater, recycled water, imported water and local surface water. These diverse sources help to keep rates low and ensure reliable supplies during times of drought, regulatory constraints and emergencies. Notably, more than half of IRWD’s supply comes from treating, purifying and reusing water , conserving precious resources and helping our customers save money. Using water efficiently helps extend water supplies in wet and dry years alike. IRWD offers cutting-edge water efficiency programs so customers have the tools needed to use water wisely. Opportunities include landscaping workshops, money-saving rebates and incentives, educational videos and outreach campaigns that aim to help customers replace their water-guzzling yards with California-friendly landscape. IRWD WATER SOURCE PORTFOLIO

445,000 POPULATION SERVED

All of Irvine & portions of Costa Mesa, Lake Forest, Newport Beach, Orange, Tustin, and unincorporated O.C. AREAS SERVED

1961 YEAR ESTABLISHED

5 PUBLICLY ELECTED MEMBERS OF THE BOARD OF DIRECTORS

DRINKING WATER CONNECTIONS 125,000

SEWER AND RECYCLED WATER CONNECTIONS 120,000

1990 Population served: 114,000 Water provided: 70,000 acre-feet

TODAY Population served: 445,000 Water provided: 86,000 acre-feet

RESIDENTIAL RATES (effective July 1, 2025)

Clear groundwater

IRWD’s rates are consistently among the lowest in Orange County.

Imported water

Recycled water

16%

18%

Tier

Rate per CCF*

Treated ground- water

14% 11%

Low Volume $2.07 (customer using 0 – 40% of budget) Base rate $2.72 (customer using 41 – 100% of budget) $7.51 (customer using 101 – 140% of budget) Inefficient Wasteful $18.60 (customer using 141%+ of budget)

Rain capture (Irvine Lake)

66%

28% 25%

Imported water

Indirect potable reuse

Recycled water

Rain capture (Irvine Lake)

*CCF = 100 cubic feet, or approximately 748 gallons

IRWD — AN OVERVIEW | IRWD.com

Michelson Water Recycling Plant

INCREASING RELIABILITY THROUGH DIVERSE WATER SOURCES GROUNDWATER More than half of the IRWD water supply comes from local groundwater wells in the Orange County Groundwater Basin. IRWD began developing local water supplies in 1979 to reduce dependence on costly imported water and now produces drinking water from 27 wells throughout the service area. IMPORTED WATER Imported water from the Metropolitan Water District of Southern California makes up less than one-fifth of the District’s supply. Drinking water imported to IRWD comes from the Sacramento-San Joaquin Delta in Northern California and from the Colorado River through the Colorado River Aqueduct. WATER BANKING Water banking — storing water in wet years for use during dry years and emergencies — is an important tool. By capturing water when it is available and storing it in groundwater basins to supplement supplies in dry years, IRWD safeguards customers from imported water supply shortages. In the event of a major and prolonged supply interruption, this stored water would be available to fulfill 100% of IRWD customers’ needs for imported water over three years. RECYCLED WATER

IRWD FACILITIES OFFICES

• IRWD Sand Canyon Administrative Offices — 15600 Sand Canyon Ave. Open 8 a.m.–5 p.m. Monday–Thursday and alternate Fridays. • IRWD Operations Center — 3512 Michelson Drive. Open 7:30 a.m.–4 p.m. Monday–Thursday. RECYCLED WATER PLANTS & STORAGE

• Michelson Water Recycling Plant • Los Alisos Water Recycling Plant

• Syphon Reservoir Improvement Project — will increase storage capacity from current 578 acre-feet to 5,000 acre-feet • Four seasonal recycled water storage reservoirs: Rattlesnake, Sand Canyon, San Joaquin, and Syphon DRINKING WATER FACILITIES • Baker Water Treatment Plant • Howiler Water Treatment Plant • Irvine Desalter Project — treats drinking water in the Irvine subbasin • Deep Aquifer Treatment System — removes color from local groundwater • Wells 21 & 22 Rehabilitation, Pipelines and Water Treatment Plant — recovers and treats local impaired groundwater for drinking use • Thirty-seven drinking water reservoirs • Dyer Road Well Field — local groundwater NON-DRINKING WATER SOURCES • El Toro Groundwater Remediation Program — provides 4,000 acre-feet of water for irrigation annually • Irvine Lake — untreated water reservoir NATURAL TREATMENT SYSTEM • IRWD operates almost 50 NTS wetlands sites, including the San Joaquin Marsh • IRWD San Joaquin Marsh Campus — including the Duck Club, Audubon House, Learning Center, Visitors Center, Sea and Sage House and Caretaker’s House

Recycled water usage

IRWD meets about a quarter of the service area’s water demands with recycled water, which reduces reliance

10%

30% 60%

on costly imported water. On average, IRWD delivers about 25 million gallons of recycled water per day to 6,000 customers through 576 miles of pipelines. The dual-distribution system, which keeps recycled water completely separate from drinking water, uses recognizable purple pipe to identify recycled water infrastructure. IRWD pioneered the use of purple pipe, which has become the international symbol for recycled water. Agriculture Business & irrigation Landscape irrigation

BUILDING SECURITY THROUGH TRANSPARENT FISCAL OPERATIONS IRWD has built secure financial standing through careful fiscal stewardship. The District uses a long- range planning approach that is similar to a family who regularly puts money aside over time to pay for the eventual cost of the children’s college education. By anticipating infrastructure needs, IRWD avoids having to dramatically increase customer rates to pay for the repair and replacement of facilities such as pipes, pumps and reservoirs as they age. To ensure equity among customers, IRWD separates the costs of building water and sewer infrastructure from the cost of daily operations and maintenance. Capital infrastructure is financed directly or through general obligation bonds, the costs for which are paid through a combination of property taxes and developer connection fees. Daily operation and maintenance costs are funded primarily by customers’ monthly water and sewer bills. IRWD rates and charges are reviewed and set by the IRWD Board of Directors. STRIVING FOR INNOVATION EVERY DAY IRWD is proud to have a state-of-the-art and state-certified Water Quality Laboratory — one of the best-equipped water labs in Southern California — right in Irvine. Our Water Quality staff continuously monitor the water supply, conducting more than a quarter million laboratory tests each year on water taken from more than 100 sample points throughout the service area. DELIVERING SAFE, HIGH-QUALITY WATER IRWD provides customers with safe, high-quality and reliable drinking water every single day. Our water meets all the exacting standards set by the state and federal governments. The annual IRWD Water Quality Report provides customers with water analysis test results and an explanation of how to interpret the information. See the full report at IRWD.com/quality . To request a copy, email info@IRWD.com or call 949-453-5500 .

ENCOURAGING EFFICIENCY WITH A BUDGET-BASED RATE STRUCTURE

IRWD uses a budget-based rate structure, which offers property-specific water budgets and tiered pricing based on the actual cost of service. The structure provides customers with economic incentives for efficient water use. Water budgets are established for each customer based on the type of home or business, irrigated landscape area, daily weather data and number of residents in the home. Customers who use water within their budget buy water in the lower tiers and enjoy low water bills. Customers who use water in excess of their budget receive a strong pricing signal indicating inefficient or wasteful use. IRWD’s monthly water rates have two components: variable water usage charges set to recapture the variable cost of imported water and local groundwater, and fixed water and sewer service charges set to recover the fixed costs of maintaining the water distribution system. This allows IRWD to provide exceptional service while also encouraging efficient water use and providing for rate stability. The monthly water charges for a typical residential customer are the lowest in Orange County.

IRWD — AN OVERVIEW | IRWD.com

PROVIDING STELLAR CUSTOMER CARE HELPING CUSTOMERS SAVE Ask the experts IRWD’s Water Efficiency department is easily accessible to answer questions and provide more information on resources and rebates available to IRWD customers. Contact 949-453-5581 or Customers experiencing problems with high water use can request a water use survey. A trained conservation specialist will visit the customer’s home, check for leaks and make recommendations for water savings. OUTREACH AND EDUCATION Community tours waterefficiency@IRWD.com . Home water survey program Anyone who lives or works in the IRWD service area can learn more about the District by attending a community tour hosted by an IRWD board member and staff. Tours are held several times a year and

San Joaquin Marsh

SUPPORTING ENVIRONMENTAL STEWARDSHIP IRWD is committed to protecting the environment through effective water and resource management. The District has adopted a variety of innovative resource management programs including water use efficiency, recycled water, energy sustainability, urban runoff reduction and treatment and public education. SAN JOAQUIN MARSH The IRWD San Joaquin Marsh encompasses more than 300 acres of coastal freshwater wetlands, 12 miles of trails and is home to more than 300 migratory bird species. The working wetlands provide a valuable wildlife habitat while naturally cleaning urban runoff from San Diego Creek — removing up to 70% of the nutrients carried in the water and helping to protect the environmentally sensitive Upper Newport Bay. The Marsh is open to the public seven days a week, year- round. Tours and educational programs are offered through community partnerships. Learn more at IRWD.com/marsh . URBAN RUNOFF AND NATURAL TREATMENT PROGRAMS Modeled after the San Joaquin Marsh, the IRWD Natural Treatment System is a series of smaller man-made wetlands that naturally remove contaminants from urban runoff in a cost-effective and environmentally sound manner. The Natural Treatment System reflects regional collaboration. IRWD partnered with service area cities, the County of Orange and local developers to build this innovative environmental project that is recognized throughout the state as a model for responsible urban runoff management. ENERGY SUSTAINABILITY IRWD recycled water and conservation programs have significant energy-efficient benefits. Imported water requires large amounts of power to move. By reducing imported water use, IRWD has cut greenhouse gas emissions. IRWD also boasts a solar energy program that further reduces the District’s carbon footprint.

publicized on IRWD.com . Community workshops

IRWD provides a variety of community programs including landscape and conservation workshops, online webinars and videos on many topics. Events are held continuously throughout the year. Registration is

available at IRWD.com/events . Water awareness education

IRWD has provided free water education programs to local students and adults since the mid-1970s — supporting learning activities in the classroom, online and out in the community to build awareness about the importance of water, its many sources and how to use it wisely. For more information, email IRWD at info@IRWD.com or call 949-493-5500 .

IRWD CONTACT INFORMATION Phone: 949-453-5300 Email: info@IRWD.com Website: IRWD.com IrvineRanchWaterDistrict

@IRWDnews @IRWDnews youtube.com/IrvineRanchWD

IRWD — AN OVERVIEW | IRWD.com

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