The State of California was expecting a triple La Niña winter this year which would have resulted in an extremely dry winter, an unfortunate forecast given the State’s historic drought conditions in 2022. Surprisingly and counter to predictions, California has had a remarkably wet winter with enough rainfall to curtail the drought and its water restrictions (yahoo!). How could the forecasts be so inaccurate and how could the water pendulum swing so far the other way? The answer is straightforward enough: our weather patterns are becoming more unpredictable, which means your SoCal tap water provider is becoming even more proactive to plan for the unplannable.
What is a La Niña and how does it impact our water supply?
La Niña, as opposed to an El Niño weather pattern, means dry weather conditions are expected, rain is not as likely as in typical years. For our area, where rain is already infrequent, La Niña cycles can cause ripple effects for our water systems. Most of the SoCal tap water providers import some water from Northern California, via the State Water Project, so when there is no snow or rain, there is less water flowing through the State’s delivery system and use of our local water sources (reservoirs, aquifers, recharge groundwater basins, desalination plants, etc.) are critical.
How did the recent rainstorms help the drought conditions?
Recent rainstorms did help alleviate current drought conditions, but since our SoCal tap water system is so multifaceted, not every drought-related impact is completely resolved. Our State’s system relies on snowmelt, which takes time to … well, melt. This runoff needs to get from the Sierra Nevada Mountains to our region. Similarly, your local watershed is replenished by rains, but the water still needs to be absorbed into the water table. Depending on conditions, it could take much more than one wet year to recover.
In March 2023, Governor Newson signed an executive order making it easier for water agencies to capture stormwater and divert it into recharge basins, a move that signals the importance of smart storage. Much like a tree falling in the woods, if rain falls where it cannot be stored or diverted, does it really help? As noted in his March 24, 2023 announcement, “We’re all in this together, and this state has taken extraordinary actions to get us to this point. The weather whiplash we’ve experienced in the past few months makes it crystal clear that Californians and our water system have to adapt to increasingly extreme swings between drought and flood. As we welcome this relief from the drought, we must remain focused on continuing our all-of-the-above approach to future-proofing California’s water supply.”
Predictions of ongoing weather swings estimate that future dry years could result in a 10% reduction in water supplies by 2040, so the state is asking water agencies like ours to prepare for hotter and dyer conditions. We will be ready.
Did the unexpected rainstorms positively impact our water agencies and water supply?
The California Department of Water Resources is now able to deliver 75% of requested water, in contrast to the 35% estimate in February, and to get ahead of the next drought, a few of our member agencies are already acting in response to the unpredictable weather shifts. Western Water is currently working to improve their stormwater, recycling and water quality programs to advance their water supply goals. Additionally, Eastern Municipal Water District will continue to actively provide a distinct water supply portfolio through their Groundwater Reliability Plus initiative, which aims to enhance the quality and amount of water in the local groundwater basins. Our safe and reliable tap water sources are the result of responsible local water sources and collaborative partnerships with the State of California, as well as Metropolitan Municipal Water District of Southern California. As our weather continues to change, consider changing your landscape to drought-resistant plants, make sure to periodically check for leaks around your house and yard, turn off your water as you brush your teeth or wash the dishes, stick to washing full loads of laundry and much more. We all have a role to play to save water, and we can make positive changes if we do it together.