San Diego and the drought: Sprinklers off, take a short shower – and desalinate

California has been drought for 20 years. San Diego is the only place in the western United States that has managed to reduce water consumption per capita – through incentives and a treatment plant.

Lush succulents, prickly palm trees, cacti, magnolia bushes – Nancy and Ken Cavanah have slipped on work gloves: Most of the native plants that the two have planted in their front yard otherwise leave clear marks with their thorns. They cut off a few dry branches, pick up withered leaves. After all: “It’s all pretty easy to care for. We don’t have to water it. That makes it easy,” says Ken Cavanah. Gardening once a month is enough.

The bungalow with attached garage is Nancy’s birthplace and stands on a typical American suburban street. The front yards are neatly tended and – apart from that of the Cavanah family – all dried up and burnt to a fairly uniform brown. Nine years ago, the couple decided: The grass in front of the door has to go, it just needed too much water. An offer from the San Diego region came at just the right time: the domestic water authority will pay a bonus of 43 dollars per square meter of garden for water-saving measures.

So 160 square meters of meadow became a drought-resistant, colorful garden landscape with mulch beds, which looks much better in the environment than the artificial turf opposite. And above all, it does not have to be watered because the native plants are very frugal. The conversion was worth it: According to their own statements, they only paid 50 dollars out of their own pocket – for a real eye-catcher on the doorstep.

Now they advertise the project in the neighborhood and offer help in filling out the applications. And if somewhere a neighbor carelessly runs the lawn sprinkler, Nancy Cavanah gets uncomfortable: “I have a mission! I think we have to save the planet together!”

Images from space show the extent

The US space agency NASA has just released new images: Lake Mead, the largest reservoir in the United States, fed by the Colorado River, viewed from space. Or rather, what’s left of it: in the past 20 years, the water level has fallen by 42 meters. A wide white bathtub rim is recognizable.

The western United States has been suffering from a mega drought for 20 years. Last year, the water allocation to the states of Arizona and Nevada was reduced for the first time.

And San Diego, California, just down the border with Mexico, had to come up with something to fight the water shortage. The result is a whole package of measures in which the city administration, water authorities and citizens are all pulling together.

In order to motivate the 3.3 million inhabitants of the region to participate, there are financial incentives to switch to water-saving shower heads and/or toilets. More than 600,000 households have registered so far – including the Cavanahs with their front yard project. In this way, 400 hectares of land were released again for more biodiversity.

Image: ARD Studio Washington

Advice instead of penalties

Leslie Payne from the Water Board regularly walks the streets with her colleagues and rings the bell when she sees a water sprinkler system running somewhere. But not to pronounce a penalty, although it is legally allowed to do so: watering the lawn in San Diego is only allowed on Tuesday and Friday evenings.

Payne focuses on education instead. She patiently explains how people can save water: turn off the sprinklers, only take a short shower, turn off the tap when brushing your teeth, use a short program on the washing machine, set up rain barrels. The list of possibilities is long.

And as small as the individual measures may seem, they are clearly having an effect. The greater San Diego region has managed to significantly reduce per capita water consumption in recent years: from 750 liters per day to less than 500 liters. Even though the city is constantly growing and although the heat and drought periods are getting longer and longer.

But as proud as the water authority is of what has been achieved so far, simply saving drinking water or groundwater is no longer enough to supply the growing cities on the US west coast.

Elaborate desalination

The second largest desalination plant in the western hemisphere has therefore been built on the Pacific Ocean just outside of San Diego. Only in Dubai is there a larger freshwater factory.

190 million liters of seawater are treated in San Diego every day to provide drinking water for the region. To do this, the salt water is sucked in in huge pipes and then pressed through many filters in ever smaller pipes – 16,000 in total. The process is called reverse osmosis.

“I could still be surfing out there in the ocean and two hours later this wave would be desalinated and come out of the tap at my house,” explains Nathan Faber enthusiastically. The water authority’s lead engineer grew up in San Diego and grew up with the ever-increasing water shortage.

All clear until 2045

Ten percent of the entire water supply currently comes from the desalination plant, and by 2035 40 percent of drinking water is expected to come from treated salt water. “A stress test has shown that we will have enough water until 2045 and maybe even longer. We’ve invested a lot in storage, desalination and the reuse of service water,” says Faber, appearing relaxed. However, environmentalists criticize the high energy consumption for desalination – and the consequences of oversalting when water is pumped back into the sea in the course of osmosis .

The city of San Diego has also invested in the seamless monitoring of the sewage system: More than 500 kilometers of pipelines have been equipped with sensors that quickly give an alarm in the event of a leak before the water can seep away.

Faber is convinced that the city’s measures will work well together. In any case, the residents of San Diego are successfully resisting the drought with these small measures – they have no other choice.

You can see this and other reports in Weltspiegel – on Sunday at 6.30 p.m. in the first.