The Future of Water on Catalina Island
2015-01-29
Catalina Island Conservancy
Over the past two weeks, we’ve gone over the basic facts of water on Catalina Island, from who owns it and is required to provide water to the basics about where and when water arrives and leaves the Island.
In this, the third article in the series, we will consider what the future of water could be on Catalina Island.
With the exception of the occasional periods when the Island’s desalinization plant is running, Catalina has relied almost exclusively on groundwater stored in shallow aquifers and provided by nature. Those of us living on the Island have especially relied on water from Catalina’s two largest Island watersheds, Cottonwood and Middle Canyons. The Cottonwood Canyon well field supplies water to the Million Gallon Tank in Two Harbors. The Middle Canyon well field supplies most of the water needed by Avalon.
Like the rest of California, the water we drink is exported from watersheds where it is found (Cottonwood and Middle Canyons) to the watersheds where it is used (Two Harbors and Avalon Canyon) through a system of pipes, pumps, tanks and reservoirs. There also wells in other locations and major canyons (e.g., Whites Landing, Toyon, El Rancho Escondido, Avalon Canyon and Howlands Landing). All of current operational wells on the Island are located in the shallow alluvial soils deposited in canyon bottoms over the millennia.
While groundwater is generally cost-effective and reliable, relying almost exclusively on it puts our local water supply and economy at risk during prolonged droughts, like the current one, when supplies can become depleted. Groundwater extraction also can have serious environmental impacts, including causing soil subsidence or sinking, saltwater intrusion into fresh water supplies, the lowering of the water table, the dewatering of perennial streams and physical habitat destruction from building pipelines, pump houses, ponds and reservoirs.
For example, in most of the Island’s canyons where groundwater is pumped, it is easy to observe formerly perennial (flowing year-round) streams on the Island that are now dry except during large rain events.
In fact, we may have exploited all of the easily accessible groundwater available in the Island’s shallow, alluvial aquifers. The recently installed new well at Howlands Landing and the new well or wells proposed to be installed in Middle Canyon are “bedrock” wells screened hundreds of feet below the alluvial soil aquifers.
For the Middle Canyon bedrock well proposal, the Conservancy has asked for the up-front study and evaluation required by the Island’s Local Coastal Plan and Title 22 of the Los Angeles County Code be undertaken before the installation in Middle Canyon of production-capable wells, which would make bedrock groundwater extraction possible.
The study would help understand the risks – which are currently unknown – of dewatering the Middle Canyon riparian and wetland ecosystem. Middle Canyon is the single largest watershed on Catalina Island. It represents nearly 20% of the Island’s land surface and has six Significant Ecological Areas specifically identified in the Island’s Local Coastal Plan which require special protection.
Another looming problem is what effect climate change will have on the Island’s natural hydrologic cycles. Regional predictions for the west in general and Southern California in particular are that our current natural cycle of wet years and drought years will change: in particular our droughts will become more frequent and/or longer. So, the periods when we exhaust the aquifers that supply most of our water will become more frequent and longer.
The Conservancy’s long-term strategic plan is titled Imagine Catalina because, in large part, we are only limited by what we can imagine and desire. So, it might be useful to close this article by imagining the kind of water system we would like to have to ensure the long-term ecological health and human livability of Catalina Island. What might such a system look like? Imagine the following:
- A water system adapted to the Island’s natural cycle of rain and drought years that could be operated so that the Island has sufficient reserves to get us through the drought years (that are a natural part of life here) without serious economic disruption or harm to the natural environment.
- A water system that would use the Island’s valuable and limited groundwater resources only for essential human uses and as a backstop for extraordinary droughts or the loss of other sources.
- A diversified water system using all viable sources of water so that we are not reliant on any one source.
- A decentralized water system for the Island’s interior that would only incorporate centralized water delivery and treatment systems where they are absolutely necessary. With existing techniques and technologies, all the camps, yacht club outstations and small interior settlements, such as Middle Ranch, Empire Landing and Airport in the Sky, could be self-reliant because they would have their own water systems. Decentralized household, apartment building and neighborhood-scale technologies could also be deployed in Avalon, especially for all non-potable uses.
Five-part water series from the Catalina Island Conservancy
Part 1: Answers to Common Questions about Catalina's Water Supply
Part 2: Facts about Catalina's Water Supplies
Part 3: The Future of Water on Catalina Island
Part 4: Ways to Increase Catalina’s Water Supply
Part 5: Making a Difference in Catalina's Water Future
By John J. Mack
John J. Mack is the Catalina Island Conservancy’s chief conservation and education officer. For more information about the Conservancy, please visit catalinaconservancy.org. The Catalina Island Conservancy has been an active participant in the Catalina Island Consortium, a group of Island stakeholders that has sought to maintain an affordable and sustainable fresh water supply for the Catalina Island community. The Consortium, working with SCE and CPUC, was recently successful in averting significant water rate increases on the Island.