Santa Monica is rushing its long-term water plan to state regulators — and giving residents just one week to weigh in.
The city is required by California law to hold a public hearing before filing its Urban Water Management Plan with the Department of Water Resources. This year, that hearing is scheduled so close to the deadline that most residents will have barely days to react to a document that will govern water policy through 2040.
Water is not an abstract concern here. Santa Monica has no rivers, no large local lakes, no natural abundance to fall back on. The city runs on three sources: local groundwater, imported water, and a growing slice of recycled and captured stormwater. Cutting dependence on imports has been the goal for decades, but outside water still flows in.
Every five years, state law requires cities to update their water management plans, projecting future demand, stress-testing supply against drought, infrastructure failure, and population growth. Annual reports keep the plan active in between. Santa Monica’s last full update was 2020. This is the next one. The public hearing is on June 23, and it is due in the state’s hands on July 1st. The public gets a week to attend the hearing and send reactions after that.
Santa Monica’s water system is built around limits. The city sits on the Southern California coast and does not have rivers or large local lakes to draw from. Instead, it relies on three main sources: local groundwater, imported water from increasingly stressed regional systems, and a smaller but growing share of recycled water and captured stormwater. Over the past several decades, Santa Monica has worked to reduce its dependence on imported water, but it still plays an important role in the system.
At present, about three-quarters of Santa Monica’s water comes from local groundwater, while roughly one-quarter is imported from regional systems. That marks a significant change from earlier decades, when imported water made up the majority of supply. The shift has come from investments in groundwater cleanup, treatment facilities, and systems that reuse water, including stormwater capture. Even so, the city is still tied to imported water. It has not reached full independence, and may never do so.
Housing growth is one of the main drivers in future water planning. Under state requirements, Santa Monica must plan for about 8,895 new housing units. According to the city’s analysis, this level of development is expected to increase water use by about 496 acre-feet per year, about 1,000 households.
That figure is lower than many people might expect. The reason is that the city does not treat new housing as a simple one-to-one increase in water demand. Instead, it uses what is called a water neutrality policy. New development is required to offset its water use by reducing consumption elsewhere in the system. That often means upgrading older buildings with more efficient fixtures or funding conservation improvements. On top of that, water use per person has been falling for years due to efficiency standards and conservation habits.
Because of these factors, the city’s projections show only a modest increase in overall demand from new housing. That increase is already built into the city’s long-term water planning. The official conclusion is that the city will have enough water to meet demand through at least 2040, even with the added housing and even during drought conditions.
Still, “enough” does not mean there is a large cushion. For one thing, there are only so many old toilets around the city that can be replaced with more efficient versions. Another limitation is storage. Santa Monica does not have large reservoirs like many other cities. Its local reservoirs only hold a few days of supply. That means the system depends heavily on continuous pumping and treatment rather than stored reserves. If part of the system fails, there is not much backup water available on site.
To maintain and improve reliability, the city has raised water rates in recent years. The money is being used to repair aging reservoirs, upgrade treatment plants, and replace parts of the distribution system. The goal is to keep the system working reliably, not to dramatically expand capacity. The city has also invested in projects that increase local supply. One example is the Sustainable Water Infrastructure Project, which captures stormwater and wastewater, treats it, and reuses it. These systems help reduce reliance on imported water, but they do not replace it entirely. Water quality in Santa Monica is closely monitored and meets all state and federal safety standards. The city conducts thousands of tests every year to make sure the system remains safe for drinking.
Even with these systems in place, there are risks ahead. One of the biggest is climate change. Much of the city’s imported water comes from Northern California and the Sierra Nevada, where snowpack feeds rivers and reservoirs. As the climate warms, snowpack is shrinking and melting earlier in the year. Droughts are also becoming more frequent and more severe.
In extended droughts, imported water supplies can be reduced. In very severe cases, deliveries could drop sharply (or even stop altogether) for long periods. If imported water were significantly limited, Santa Monica would have to rely much more heavily on groundwater and recycled water. Those systems are important, but they were not originally designed to supply the entire city on their own.
Another uncertainty is whether future housing growth will match the assumptions in the city’s water plan. The current planning is based on about 8,895 new units, as required by the state. But actual development does not always follow those exact numbers. If more housing is built than calculated for, especially through rules that require affordable units as part of larger market-rate projects, then water demand could be much higher than the current plan assumes. In that case, the city would likely need to drastically revise its water projections and dramatically overhaul its conservation or supply strategies.
Overall, Santa Monica’s water system is stable under current assumptions, but it operates with limited room for error. It depends on a mix of local supply, imported water, conservation, and infrastructure that must all function together. The system is not failing, but it is also not flexible enough to absorb large surprises without major and possibly extremely difficult adjustments.
Daniel Jansenson, Architect, for S.M.a.r.t.: Santa Monica Architects for a Responsible Tomorrow.
Dan Jansenson, Architect, (former Building & Fire-Life Safety Commissioner); Robert H. Taylor, Architect AIA; Mario Fonda-Bonardi, Architect AIA (former Planning Commissioner); Sam Tolkin, Architect, (former Planning Commissioner); Michael Jolly ARE-CRE; Jack Hillbrand AIA, Landmarks Commission Architect; Phil Brock (SM Mayor, ret.); Matt Hoefler, Architect NCARB; Heather Thomason, community organizer, Charles Andrews columnist, journalist.
