NATURAL PERSPECTIVES:
Storms don’t mean end of drought
Heavy rains of last week notwithstanding, we still live in a desert and should act accordingly
By Vic Leipzig and Lou Murray
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It’s official. National Weather Service forecasters say that a strong El Niño condition has developed in the Pacific Ocean. That means we’ll be having above-average rainfall here in the Southland over the next two, or maybe even three, months. If last week was any foreshadowing, this could be a doozy of a spring.
The storms of last week left a lot of fresh snow in the Sierras, which is great for our imported water supply. Right now, the Sierra snowpack is a tad above average. But mountain reservoirs are still well below what we need to be comfortable. Watering restrictions are still in effect. Also, the Diemer
Filtration Plant, which purifies our imported water, is partially shutting down for installation of an ozone treatment system from Jan. 25 to 31, so extra conservation measures are called for this week.
It is hard to believe that we could be in a drought. The snow fell so heavily in Big Bear last week that fuel and grocery delivery trucks couldn’t get through. Roads were closed on Sunday just to give the town time to restock. While that was bad news for skiers and resort operators, all that extra snow bodes well for our future local water supply.
Snow in Big Bear eventually results in snowmelt that goes into the Santa Ana River. If you want to see the Santa Ana River in its wild and natural state, go to Angelus Oaks this spring and take Glass Road down to the river. It’s an awesome sight to see the Santa Ana River tumbling free and wild over big granite boulders. White alders grow along the creek banks with columbine and cardinal monkeyflower blooming in profusion. The river there looks nothing like it does as it passes by Huntington Beach in a concrete-lined channel.
The water in the Santa Ana River travels down the mountains, across the plains in Riverside, and into Prado Dam. From there, it is released slowly to travel downstream from Yorba Linda to Santa Ana. There, it disappears into the sandy riverbed. The goal of the water managers is to release the water just slowly enough that it seeps into the ground to recharge the groundwater basin, but not so fast that it makes it all the way to the ocean.
Last week, that goal wasn’t met. In order to maintain some extra water storage capacity behind the dam for flood control, the water managers had to release water at a rate of 1 million gallons a minute. That level of discharge allows water to flow all the way to the ocean, and out of our grasp. What a waste.
Vic and I collected and stored a lot of water from last week’s rainfall, about 230 gallons. I’ll use it later when my vegetable garden and fruit trees need water. But I felt that my efforts to store water were pretty puny compared to 1 million gallons a minute rushing to the ocean. You’d think that in times of drought when mandatory water restrictions are in place, the water managers could flex a bit on how much water they store behind the dams. For flood control, they’re supposed to discharge water when the dam reaches 80% capacity. Maybe they could change that to 85% when we’re in a severe drought.
It sure would be nice if the rain would space itself out a bit more instead of coming all at once. But that doesn’t seem to be the way Mother Nature works. When it comes to water in Southern California, it’s feast or famine, flood or drought. What is really hard to grasp is how we can be in a drought when we have all this gosh-darn rain pouring down on us.
The answer lies partly in the Rockies, partly in the Colorado River storage basins of Lake Mead and Lake Powell, and partly in the fact that we have 14 million people living in the Greater Los Angeles Area. Like the Sierras, the Rockies don’t have as much snow as usual. Global warming, whether you believe in it or not, is causing profound changes in the snowpack of the Rockies as well as the Sierras. We rely on imported water from both of these places because our groundwater just isn’t plentiful enough for all of the people who now live here.
Precipitation comes as rain rather than snow more often now, which diminishes the snowpack. Snow falls later in the season and melts earlier. When water runs off all at once instead of being stored in the form of snowpack, it can overwhelm storage dams. Excess water is released. But right now, that release seems to be happening only along the Santa Ana River watershed. Lake Mead and Lake Powell along the Colorado River are only at 50% capacity. Dams in the Sierras are also well below capacity.
The bottom line is that the climate is changing. Climatologists predict extended droughts for the entire Southwest. The Rockies and Sierras will get less precipitation overall, and that precipitation will increasingly come as rain rather than snow. That does not bode well for the future of agriculture in California, nor for water-thirsty landscaping in Southern California yards and parks.
So despite the rain that has fallen the past couple of weeks, and that is anticipated to fall over the next two months, we live in a desert. Our normal average rainfall is only 15 inches a year. That is not enough moisture to support grassy lawns, which require 52 inches of water a year. We all need to move toward drought-tolerant landscaping. We need to conserve water in as many ways as possible, whether by planting California native or other drought-tolerant plants, setting up rain barrels to collect rainwater, not flushing every time the toilet is used, taking shorter showers, or washing dishes and laundry only when there is a full load.
Even if we end up getting 30 inches of rain this year, the drought isn’t over. It will have just been postponed. Big change is coming, and we need to adapt to changing climate conditions.
VIC LEIPZIG and LOU MURRAY are Huntington Beach residents and environmentalists. They can be reached at LMurrayPhD@gmail.com .
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