Volume 3 - Issue 12 | September 2022
What is Flood Irrigation?
by Allison Weber
The goal of the Keep Long Valley Green Coalition is to maintain historical irrigation on Los Angeles Department of Water and Power (LADWP) agricultural leases in Long Valley and Little Round Valley–but what does that irrigation even look like?
September is the beginning of the end for Long Valley “meadow muffins,” the cows that graze on the summertime’s green irrigated meadows and wetlands along the upper Owens River north of Crowley Lake. Off of Benton Crossing, you are likely to see cowboys rounding up the cattle whose numbers abound with summer’s plenty and packing them off for new homes as the fall breeze sets in. The last of the herd, mothers and named family favorites, are left to clean up the remaining grasses, a smaller herd on the land as all get ready for the cold season.
The last of the cows will remain until late October when the local ranchers bring them back down the hill to warmer climes in Northern Inyo County. It is at this time that all in Mono and Inyo County, ranchers, fisherman, skiers, and more, hope for a great winter to come in the mountains. Snowpack is the lifeblood of the Eastern Sierra, melting through the beautiful alpine creeks and canyons down to the Owens Valley floor. It is this snowpack that makes the wetlands habitat and irrigated meadows of Long Valley possible.
Headwaters in the mountains become local creeks that flow into the Upper Owens River. From here, one of the oldest irrigation methods, flood irrigation, is applied. Flood irrigation, also known as surface irrigation or furrow irrigation, models after the natural processes of flood and growth along riverbanks, where much of traditional agriculture has taken place due to the fertile sediments left behind by rivers and their flooding/retreat patterns.
This traditional method is not considered as efficient as more industrial sprinkler systems. However, in dry ecosystems like the Eastern Sierra, one can expect to lose more water to evaporation with a sprinkler system; flood irrigation, on the other hand, is considered to lose more water as runoff. This runoff can be wasteful in crop production, but in Long Valley and Little Round Valley, this water grows grasses for livestock to graze with any excess providing life for the wild plants and animals that call the Long Valley caldera home. The ranchers also use the natural grading of the hilly landscape to move excess water from farther up the valley down to the meadows.
Irrigation starts with a simple diversion in the Owens River, with a built-up wall of rocks directing the water to flow away from the river and towards the meadows, under the fencing which protects the riverbanks from the cows’ tread. An LADWP meter constantly measures the flow of the water through the meadow chute. How much water flows through the irrigation ditches and in which ditches it flows is determined by hand, with the ranchers physically blocking and unblocking the ditches with wood slats or metal lids.
Right An LADWP measuring station on an Upper Owens River Diversion
The water is applied when the cows are elsewhere: While one meadow is being irrigated and allowed to grow, another is being mowed down by the cattle. This prevents damage to the soil when wet but also allows the meadows to rest and grow again, using the land's natural cycles of growth to increase productivity.
Flood irrigation organically provides other co-benefits. As the ranchers walk through the meadows to determine where the water is needed throughout the season and change up the flows accordingly, they also assess the meadows' other needs. With shovels, rakes, rocks, and a watchful eye, irrigating becomes a key time to note maintenance required and to steward the land, whether it be cleaning up after cows, preventing erosion (water is a powerful erosive tool, and cows, like water, and people, like to follow the easiest ways through the meadows), removing invasive plants, or even cleaning up after illegal dispersed camping.
A bank juts out into the Upper Owens River, forking a small amount of water towards the irrigation ditches on the Kemp family lease. In the foreground, stinging nettle and rabbitbrush, both invasive, can be seen on the left and right, respectively, in an area fenced off from cattle. In 2018, when LADWP allowed the ranchers only 0.71 acre feet of water, these 2 species abounded in Long Valley as they pushed out the usual grasses which need more water to grow.
LADWP needs to realize this water is not worth only the grasses and livestock it can produce, nor the decrease in cost for ratepayers if LADWP were to keep it for itself. This irrigation water is also worth its ability to prevent and address key concerns in agriculture such as overdrafted groundwater and unhealthy soils, both of which are even more critical concerns in times of drought. The runoff associated with flood irrigation can help recharge groundwater aquifers while replenishing the stores of water within soil pores, the spaces between each soil particle.
LADWP claims it needs the water in Long Valley and Little Round Valley due to drought stress, but returning water to parched soils is especially important during dry spells. Should the land in Long Valley and Little Round Valley be dewatered, it could lead to significant soil absorption problems. Healthy soils are like a sponge, capturing and storing water. Dry, packed soil resulting from dewatering would no longer accept water in natural wet years. With increased climate variability, we can expect to see more dramatic “feast and famine” years, with drought followed by heavy precipitation, making it more important than ever to steward soils for health and absorption.
LADWP should know the importance of this regulation: In the large water year of 2016-2017, following the severe drought of 2012-2016, the agency worked with ranchers in Long Valley to spread more water than usual. In LADWP's perfect world, the excess water of big years would all flow to LA, but the truth of the matter is that their infrastructure simply cannot handle such large flows, and so they rely on the folks working their ranch leases to spread the excess before it goes through the aqueduct. Should the soils be degraded as a result of LADWP removing all or most irrigation in drought years, this kind of management would not be possible, with the soil having lost its sponge like abilities. Erosion problems will follow when the water of big years cannot penetrate the soil and, as a result, simply has nowhere to go.
Just as we are now experiencing extreme drought, we can expect big years like 2017, following multiple year droughts, in the future. Continuing irrigation on these lands, even in drier years, helps us mitigate these extremes and maintain some regularity/consistency in our environment.
Creating this consistency means tightening our belts in water use: both in the Eastern Sierra and southern California. LADWP claims that with decreasing snowmelt they have little water to spare, but seeing how this water is coming from the Eastern Sierra ecosystem, the real matter is how much water the Eastern Sierra can spare for LA, not the other way around. Water for Eastern Sierra ecosystems and livelihoods is not superfluous, unnecessary, or “spare.” It is the starting point. Together these entwined communities can manage Eastern Sierra water for the protection of our future. It starts with preventing further degradation. It starts with keeping Long Valley and Little Round Valley green.
October 5th: Monty Bengochia Celebration of Life and Film Screening in Lone Pine
In Lone Pine for the Lone Pine Film Festival? Join Keep Long Valley Green the night before, Wednesday October 5th, for a free film screening and celebration of life for Monty Bengochia, long time Eastern Sierra water activist and Commissioner for over 30 years on the Owens Valley Indian Water Commission. Monty was instrumental in guiding and educating anyone who worked in water issues in the Eastern Sierra/Payahuunadü, including all of us at Keep Long Valley Green, and was involved in the production of Without Water. It is his voice that beautifully closes the film, which will be shown at the Lone Pine Museum of Western Film History.
October 15th: Join Us for Our First Adopt-A-Highway Cleanup!
Driving through Long Valley on the 395 you might have noticed our new Adopt-A-Highway sign courtesy of local business Sweet Water Hideaway. Now it is time for our first clean up! Join us at 9:00 AM on Saturday, October 15th, with coffee and donuts provided. RSVP below.
September Wrap-Up:
Without Water made its Burning Man premiere as part of the Black Rock City Film Festival August 29th-September 5th and then its Island premiere at the Catalina Film Festival, September 24th, connecting 2 unique and threatened ecosystems: Catalina Island and the Eastern Sierra. Following the live festival, Without Water is available to stream from September 30th-October 10th as part of the virtual section of the Catalina Film Festival.
Keep Long Valley Green participated in the California Native American Day Parade on September 23rd in Bishop as part of the Pabanamanina PowWow, walking alongside with Friends of the Inyo and Protect Conglomerate Mesa.
Without Water was also well received at The Village in Mammoth Lakes for the Mammoth Trail Fest on September 24th, with Keep Long Valley Green Coalition Organizer Allison Weber and Executive Director of Friends of the Inyo Wendy Schneider presenting and answering audience questions. Afterwards, Weber moderated a panel for National Public Lands Day.
The panel focused on how runners (and any outdoor community) can involve themselves in the stewardship of the lands they use and featured Vic Thasiah, founder and Chief Advocacy Officer of Runners for Public Lands (RPL), Kamilah Journét Vice President of RPL's Board of Directors, Dakota Jones, founder and Executive Director of Footprints Running Camp, and Nate Bender, Footprint's Marketing Director. With Footprints and RPL both focusing on how to educate runners on environmental challenges and connect runners to conservation efforts, Weber highlighted the many organizations, clubs, and individuals who run the dirt roads of Long Valley without ever knowing the threat these meadows face nor the effects that dewatering would have on their ability to run in these areas.
The panel was a success and Keep Long Valley Green looks forward to working with these two great organizations again in the future, at next year's Trail Fest and beyond.
Credits:
Allison Weber photo credits