Sustainable Water Master Plan Executive Summary

Executive Summary

The City of Santa Monica (City) supplies imported and local water to approximately 91,000 residents covering an area of approximately 8 square miles. Looking to its future, the City hopes to eliminate its reliability on imported water by addressing the challenge of existing groundwater quality, identifying new sources of local water supply, and more effectively reduce and manage its water demands.

With an adopted goal of water self-sufficiency achieved by eliminating reliance on MWD supply by 2020, the City of Santa Monica retained Kennedy/Jenks Consultants to develop an integrated Sustainable Water Master Plan.  This Master Plan combines relevant components of existing plans with an evaluation of a broad range of water supply and demand management options to assist the City in meeting its goals. This plan has been prepared with the objective of developing a comprehensive document to define supply and demand management options to cost effectively reduce future water demands and enhance local water supply production capabilities. 

Goals and Purpose

The purpose of this planning effort is to provide an up-to-date, comprehensive look at the City’s water system using recent planning information and the newly-developed distribution system hydraulic model to assess the City’s water system infrastructure needs.  In a March 2011 study session with the City Council, staff presented concepts and principles that would be involved in achieving water self-sufficiency goal by the year 2020.  Since that time, the City has embarked on the development of a sustainable and proactive plan to accomplish this goal. 

This Sustainable Water Master Plan (SWMP) includes an evaluation of expanded demand management measures and a variety of water supply alternatives including recycled water, storm water collection and treatment, rainwater harvesting, gray-water applications, and other water rights, supply and exchange opportunities to align with the above goal.  A decision modeling approach was used to package these programs and projects into Supply-Demand Portfolios, where criteria were developed to provide portfolio ranking, economic analysis and ultimately, strategic direction.  This plan illustrates projected water supply and demand scenarios, and characterizes the approximate magnitude of supply deficits or unpredictability that needs to be addressed to meet the City’s self-sufficiency objectives by 2020.  The recommendations resulting from this SWMP are designed to provide a roadmap of phased projects and programs to guide the City’s water utility towards self-sufficiency. 

Implementation of the SWMP is further supported through the conduct of financial planning services.  These services, prepared and documented under a separate cover, included an evaluation of water and wastewater rates, rate structures for conservation support and financial stability, and an update to the City’s water and wastewater facility capacity charges. 

As discussed above, the development of a Sustainable Water Master Plan (SWMP) entails a multi-faceted approach to address the City’s goal of achieving water self-sufficiency by the year 2020.  With the City’s current capability to meet approximately 70% of its water demand from local groundwater sources, the objective is to develop strategies to close the “gap” represented by the current purchase of imported water.  Through a combination of demand management approaches and water supply augmentation tactics, various portfolios were developed to represent permutations and combinations of options that best meet the program objectives and continue to support the City’s Sustainability Plan.  The SWMP documents the mix of strategies that could be undertaken to achieve water self-sufficiency by 2020, and recommends a portfolio of conservation/supply programs and capital projects to meet these self-sufficiency goals.  

A summary of the primary goals of this project include:

·      Perform a water demand analysis and generate water demand projections, which incorporate the most current information regarding population, land use and LUCE information for the City’s service area projected to the year 2035. The water demand projections consider the effects of weather and economic conditions on future water demand in order to increase defensibility in a time of increased pressure to reduce potable water demands in response to State legislation,

·      Conduct a rigorous evaluation of the City’s current and future Supply Alternatives and Demand Management Options to be able to build strategic Portfolios of for future,

·      Develop a comprehensive potable water system hydraulic model development, including calibration, and perform a hydraulic analysis under various system conditions,

·      Perform an evaluation of infrastructure improvements to accommodate existing requirements and meet future needs, including an evaluation of system infrastructure fire flow (FF) requirements, and an updated capital improvement program to support the City's short and long-range capital improvement requirements,

·      Perform a comprehensive financial evaluation of the City’s water and wastewater utilities and associated rates and rate structures, and

·      Prepare and submit two separate reports documenting the findings and recommendations of the Sustainable Water Master Plan and the Water and Wastewater Rate and Revenue Study. 

Service Area Description

Santa Monica is a beachfront city in western Los Angeles County. It is situated on the Santa Monica Bay, and is surrounded by the city of Los Angeles on the Northeast, the Pacific Ocean on the west, Mar Vista on the east and Venice on the southeast. The City’s service area consists entirely of the City of Santa Monica with limited service in the City of Los Angeles. The City occupies 8.3 square miles (5,312 acres) of land. Figure ES-1 shows the Santa Monica City boundary and the vicinity areas.

Figure ES-1 Santa Monica Boundary and Vicinity Map



The City of Santa Monica (City) provides water service to approximately 91,000 residents through a combination of local and imported water supplies.  In recent years the City has relied heavily upon Metropolitan Water District (MWD) water (referred as imported water in this report) due to the presence of contamination in its groundwater supply, necessitating additional local groundwater treatment.  Due to recent studies and efforts to mitigate this contamination, the City has started bringing wells back online and pumping more groundwater, which is helping create a more robust, reliable supply of water.  The City has also continued to collect and recycle dry-weather urban runoff for use as a treated non-potable water source.

In terms of land use classification, single family and multi-family residential are the City’s predominant user type. In addition to the residential land-use, the City also has centralized business, a commercial district, and institutional and industrial areas. Figure ES-2 below shows the current land-use map of the City. It is expected that future changes in growth and land-use type will result from re-development of the existing parcels since almost all of the City’s area is at near built-out conditions.


Figure ES-2 Santa Monica Landuse Map


Growth in Santa Monica

Given the near build-out condition, population growth in the City’s service area is projected to be minimal, less than 1 percent per year.  As a major commercial center for the region, the City experiences daytime populations of up to 200,000 due, in large part, to the number of businesses and attractions located within the City. This increase in population along with general non-residential growth rate will increase the City’s water demands for indoor and outdoor use in future years.  Table ES-1 below shows the City’s projected population through the 2035 planning period. 


Table ES-1 Projected Population







Projected Population






Source: 2010 Urban Water Management Plan.


Historical Water Demands

Since 2005, water demands within the City have ranged from 13,000 AF to 15,000 AF with an average annual demand of approximately 13, 930 AF (Table ES-2). The decrease in demands that began in 2008 corresponds with statewide drought conditions promoting the need to conserve water resources and depressed economic conditions..  Overall, the City’s water use has been steadily declining since the early 1990’s as a result of its successful water conservation programs.


Table ES-2 Historic Water Use


Demand (AF)(a)





















(a)    Source of data for years 2005-2009: City’s 2010 UWMP. Source of data for years 2010-2013: City’s Department of Water Resources Public Water System Statistics report.



The City provides water service through over 18,000 metered service connections to a variety of customer types.  These include: residential, commercial, institutional, and landscape customers. Approximately 80 percent of the City’s total service connections are used to serve the City’s residential customers.  Commercial and institutional accounts account for approximately 12 percent of the service connections.  Landscape irrigation, fire line services and various “other” accounts make up the remaining 8 percent of the City’s water customers. Among the “other” accounts is a very small set of customers receiving recycled water from the Santa Monica Urban Runoff Recycling Facility (SMURRF).   A graphical summary of the water usage by customer type is shown in Figure ES-3. 

Figure ES-3 Service Connections by Customer Type

Source: City utility billing data; calendar year 2013


As expected, the majority of the City’s water use occurs within the residential sector (Table ES-3).  As shown, residential usage accounts for approximately 61 percent of the City’s total consumption.   



Table ES-3 Historic Water Demand by Customer Type (AF)

Customer Type










Single Family Residential










Multi-Family Residential




















Landscape Irrigation(a)










Unaccounted for Water(b)










Total Water Use(c)










(a)    Includes recycled water produced by the SMURRF.

(b)    Unaccounted water for 2012 and 2013 based on average of unaccounted water from 2005 to 2011

(c)    Source of data for years 2005-2009: City’s 2010 UWMP. Source of data for years 2010 and 2011: City’s Department of Water Resources Public Water System Statistics report (“Total water into the system,” including recycled water).


Water Demand Analysis and Projected Future Demands

To achieve water self-sufficiency by the year 2020, the City must have a clear understanding of its future water needs, or demands. The total amount of local water supplies needed to meet the City’s sustainability goal includes water supplied to customers as well as an allowance for system water loss, and water lost through the water treatment process referred to as brine or production loss. 

The City’s initial estimate of the volume of water needed to meet the sustainability goal was approximately 3,700 acre-feet (AF); however, that estimate was based on the assumption that water demand would not increase in the future beyond current levels and did not consider the effects that economic activity and weather may have on historical and future water demands. While the extent of these effects may vary based on local conditions, there is a general increase in demands with increased economic activity and hotter, drier weather conditions.  These effects were not incorporated in the demand projections available in current planning documents, including the 2010 Land Use and Circulation Element (LUCE). 

To plan for future water supply needs, a comprehensive demand analysis was performed that reconciled prior demand projections with actual water usage in the last several years, and were adjusted for the potential effects of weather and economic activity applicable to Santa Monica.  First, a new baseline demand projection was developed. This baseline demand projection begins with current actual demands of approximately 13,500 AF in 2012 and grows at the same rate as the water demand projection found in the LUCE.  LUCE annual growth rates were used since it was developed based on the City's best estimates of demographic and development projections used in the City’s General Plan and other planning documents. Figure ES-4 compares the water demand projection found in the LUCE with the new baseline demand projection.


Figure ES-4 LUCE and Baseline Water Demand Projections







Next, the effects of weather and economic conditions on the City’s water demand were explored. Regression analyses were performed to evaluate the correlation between water use for various customer categories (single family, multi-family, commercial, institutional and landscape irrigation) and weather and economic (unemployment rate) factors.  Data from the regression analyses indicated that there was no significant correlation observed with weather related parameters for the City.  However, a better correlation was found between the City’s unemployment rate and the water use of single family, multi-family and landscape irrigation customer classes.  A decrease in the unemployment rate resulted in an increase in water use among these customers.  The analysis suggests that an element of the City’s reduction in water usage was due to the recent recession and higher unemployment rate. 

Accordingly, the baseline water demand was adjusted to project future water demands under good economic conditions, as shown in Figure ES-5.  The “good economy” demand projection is approximately 10 percent higher than the baseline water demand projection.  Given that the City’s existing local water supply capacity is approximately 9,000 AF, the demand analysis suggests that the gap between available local water supply from the Arcadia Water Treatment Plant, and the volume of water required to meet the City’s sustainability goal in 2020 is actually closer to 6,500 AFY, rather than 3,700 AFY.


Figure ES-5 Comparison of Alternative Demand Projections








Water Conservation Analysis and Effect on Future Demands

Water conservation modeling and analysis was performed to better define the City's opportunities to reduce the projected water demands described above through the implementation of water conservation programs. Following the completion of a detailed billing and historical conservation program and policy analysis, a comprehensive list of water conservation programs was developed and modeled using the Alliance for Water Efficiency’s Water Conservation Tracking Tool. This model allows users to analyze the water savings potential and implementation costs of a collection of water conservation programs. The model also uses local demographic and housing characteristics to estimate water savings that could be attributable to enhanced efficiency requirements in State plumbing codes and water fixture usage standards, and predict reductions in demand from other applicable programs.  

The suite of programs selected for analysis address each of the City’s water customer sectors (single-family, multi-family, commercial, institutional, and landscape) with an emphasis on water users that shows opportunity for additional conservation.  Since 1988, the City has invested millions of dollars in resources to retrofit nearly every indoor plumbing fixture in commercial, single-family and multi-family buildings with water saving products.  As a result, water usage in the City has declined even though the City’s population and non-residential development have increased.

Results of the billing analysis indicated that the greatest remaining potential for water conservation exists among the City’s commercial and institutional customers, as well as in landscape water use. Two specific large water users, St. John’s Medical Center, the Santa Monica-Malibu Unified School District, and laundry facilities, were identified by City staff as customers with a high potential for additional water savings and programs were developed to target those potential water saving opportunities.

Implementation levels for each water conservation program modeled were based on analyses of saturation rate of existing water saving plumbing fixtures and landscapes, customer surveys, staff knowledge of the City’s customers and their willingness to implement these programs, and products that will have long-term water savings that are not dependent on significant changes in the customer’s behavior. The goal was to develop a diverse selection of programs that aggressively pursued demand reduction through retrofitting existing indoor plumbing with plumbing fixtures that save about twenty percent more water in addition to retrofitting landscape customers’ with plants and irrigation approaches that can save up to eighty percent more water, compared to existing landscapes.

The resulting suite of conservation programs, shown in Table ES-4, is projected to save approximately 775 AFY of water in the year 2020.  An additional 418 AFY of savings is expected in 2020 as a result of State plumbing and building code standards that require higher water saving fixtures. In addition, a reduction in system-wide leaks and non-revenue water through capital investment in the system is projected to save another 250 AFY of water for a total demand reduction of approximately 1,443 AFY in 2020.

Table ES-4 Water Conservation Programs



Figure ES-6 shows the potential effect of implementing the recommended water conservation programs on the City’s projected water demand assuming the “good economy” water demand projection previously described. Implementation of the recommended water conservation programs reduces the volume of additional water the City must produce to meet its self-sufficiency goals from approximately 6,500 AF to approximately 5,000 AF. While water conservation alone will not enable the City to meet its water self-sufficiency goal, it can significantly reduce the volume of additional water supply required.

Figure ES-6 Demand Reduction from Recommended Conservation Programs


While conservation programs are often less expensive than physically constructing and operating new water supply or treatment facilities, the noted reductions in projected water demand are not without a cost.  For the City of Santa Monica, these costs include the cost of the actual conservation program, increased staff and public outreach costs associated with new program implementation and management, and the associated loss in water sales revenues (this latter component is partially offset by reduced water supply production costs).  Based on the City's current demands and water revenues, it is estimated that the total cost for the recommended water conservation program reflected in Table ES-6 is approximately $7.2 million through 2020.

Water Supply Analysis

Given the City’s projected water supply demand conditions, a multi-faceted water supply portfolio is needed to meet the City’s water self-sufficiency goal.  This portfolio is projected to include both demand reduction measures through the implementation of water conservation programs, as well as new supply and water treatment options. New water supply options may include additional groundwater capacity, rainwater harvesting and stormwater capture, and additional recycled water sources. These current and future supply options are explored in greater detail herein.

Current Water Supply

The City’s existing water supply consists of groundwater, purchased imported water, and a small amount of recycled dry weather urban runoff.  Historically, groundwater made up the majority of the City’s water supply portfolio; however, in 1995 when methyl tertiary butyl ether (MTBE) contamination was discovered in the Charnock Sub-basin, a sub-basin of the Santa Monica Basin, the City was forced to shut down five groundwater wells and purchase the majority of its water supply from MWD.  In addition to local groundwater and purchased imported water, the City treats a small volume of dry weather urban runoff, yielding a source of recycled water that can be used for landscape irrigation and other approved uses, such as toilet flushing.

Imported Water

In recent years the main source of potable water supply for the City has been imported water purchased from MWD.  MWD receives a negotiated allotment of water from the Colorado River and the San Joaquin River Delta.  These allotments are then distributed among its 26 member agencies – a cooperative of municipalities and water agencies located throughout southern California. 

The City has a current Tier 1 rate allocation of 11,515 AFY of water through MWD. Tier 1 water corresponds to the amount of water the City is entitled to purchase at the Tier 1 rate.  MWD Tier 2 water is also normally available to the City; however, the cost per acre-foot is higher and there is less availability and reliability of Tier 2 water in periods of drought. The City has routinely exceeded its Tier 1 entitlement in recent years due to inactivity of many of its wells.  Prior to the recent reactivation of its groundwater production, imported water represented approximately 85 percent of the City’s total water supply. Table ES-5 shows the City’s imported water purchases since 2005.


Table ES-5 Historical Imported Water Supply


Purchases (AF)



















Source: City of Santa Monica Water Resources


The City maintains two separate connections with MWD for its supply of imported water. These two connections are shown in Table ES-6.

Table ES-6 City of Santa Monica's MWD Connection Capacities




Total Capacity

Capacity (AFY)






Local Groundwater 

Local groundwater represents both an existing source of potable water as well as a potential source of future potable water supply.  Local groundwater has, until recently, been underutilized due to the shutdown of five Charnock wells that reported MTBE contamination in 1995. Due to the completion of MTBE remediation efforts in February of 2011, the City has been able to bring the five Charnock wells back online. 

The City obtains its groundwater supply from the Santa Monica Basin (Basin). The Basin is located in western Los Angeles County and overlies the entire City of Santa Monica, Culver City, Beverly Hills, and portions of western Los Angeles. The Basin has a surface area of 50.2 square miles and consists mostly of flat to mildly hilly terrain. The basin is bounded by impermeable rocks of the Santa Monica Mountains to the north, the Ballona Escarpment (Bluffs) to the south, the Newport-Inglewood fault to the East, and the Pacific Ocean to the West. Extensive faulting within the Basin separates it into five subbasins as shown in Figure ES-7 below.






Figure ES-7 Local Groundwater Basins and Subbasins

Groundwater in the Basin is replenished by percolation from precipitation, receiving an average annual precipitation of about 14 inches, and by surface runoff from the Santa Monica Mountains. Since the basin is mostly urbanized and soil surfaces have been paved to construct roads, buildings, and flood channels, only a small portion of basin soils are capable of transmitting water to the water-bearing formations below.

The City has historically pumped annual volumes of groundwater ranging between 11 and 10,038 AF, with a long-term average volume of 4,277 AFY. The combined capacity of the City’s five wells located in the Charnock Sub-basin is 9,000 GPM.  An additional five wells, two in the Arcadia Sub-basin and 3 in the Olympic Sub-basin, remained online when the Charnock wells were shut down, and have the ability to produce 3,300 GPM. These five wells have been responsible for approximately 1,950 AFY, or 13 percent of the City’s water supply. In total, the City currently has the ability to pump groundwater at a rate of approximately 10,600 GPM.  Table ES-7 shows the capacity of each of the City’s groundwater wells.


Table ES-7 Groundwater Well Capacities

Well Name/No.


Capacity (gpm)

Charnock 13



Charnock 16



Charnock 18



Charnock 19



Charnock 20



Arcadia 4



Arcadia 5



Santa Monica 1



Santa Monica 3



Santa Monica 4




Total Capacity


Source: City of Santa Monica Water Resources.  Capacities are average values and vary over time.

Non Potable Water 

To protect the Santa Monica Bay from contamination caused by pollutants found in dry weather urban runoff the City built the Santa Monica Urban Runoff Recycling Facility (SMURRF).  The SMURRF project produces a small volume of high-quality recycled water that is used to offset potable water demands for landscape irrigation and indoor plumbing.  Designed to routinely treat 0.5 MGD, with a peak treatment capacity of 0.75 MGD, the SMURRF removes urban contaminants and treats the influent water to Title 22 state standards for tertiary water. The water is then pumped through a separate water distribution system to serve a number of parks, medians, Woodlawn Cemetery and some dual-plumbed buildings.

The SMURRF has allowed the City to slightly reduce its reliance upon MWD water at a time when the City relied heavily upon imported water due to the lack of production from groundwater wells.  However, since dry weather urban runoff is an unstable supply, the focus of this facility has been predominantly water quality improvements to Santa Monica Bay.  Historically, SMURRF has had an average production of 154 AFY, with a high of 354 AF and a low of 94 AF.

Future Opportunities and Portfolio Development

Additional Local Groundwater Opportunities

In addition to implementing the water conservation programs previously described, the City is also desirous of expanding use of its local groundwater resources. Currently, the City obtains local groundwater from the Arcadia Olympic Sub - basins via five wells.  These wells can produce approximately 3,000 acre feet per year (AFY).  Additionally, there are five wells located outside of the City limits in the Charnock Sub-basin with a combined average production capacity of approximately 6,000 AFY.  From 1995 to 2010, the City purchased most of its annual water supply needs from the Metropolitan Water District (MWD) as the Charnock well field was shut down due to methyl tertiary butyl ether (MTBE) contamination. The total average groundwater production capacity from these sub-basins for local treatment at the Arcadia Water Treatment Plant is approximately 9,000 AFY.

Another study of the groundwater basin was recently performed by Richard C. Slade and Associates, LLC (RCS).  The study suggests the City may have additional local groundwater opportunities within the Olympic, Charnock and Coastal Sub-basins.  The Coastal sub-basin has not been utilized as a groundwater source to date due to salt water intrusion; additional treatment would be required to utilize water from this basin. Additional efforts are needed to assess potential sites and derive the potential quality and quantity of additional well production for the City's supply portfolio.  Incorporating the RCS study with the SWMP’s evaluations and discussions, has led to the following preliminary recommendations for additional local groundwater production and treatment facilities.  These preliminary recommendations are:

While additional engineering and hydrogeologic studies will be required to determine a realistic production capacity for these wells, it is believed that the City could attain as much as an additional 6,000 AFY of local water if all of these strategies were implemented. Of course, an equivalent increase in local water treatment capacity is required to deliver this water to the City's customers, requiring an increase in the capacity of the Arcadia Water Treatment Plant and/or using settlement funds and other sources to construct a new water treatment plant (currently referred to as the Olympic Water Treatment Plant as it is designed to focus on treating water from the Olympic sub-basin).  The current approach for siting some of these future water supplies is reflected graphically on Figure ES-8. 

Figure ES-8 Groundwater Basins and Facilities