Can Plastic Bags Slake City's Thirst?

— It's very easy to take water for granted. Even here, in arid San Diego, when you turn on the tap, water always issues. But the fact is, only about 5 percent of the water in the tub during your last bath fell to the ground as rain within San Diego County. "We import almost all of our water," says Kurt Kidman, spokesman for the City of San Diego Water Department. "It has been well over 90 percent the last few years."

About half of the water imported into San Diego comes from the Colorado River. The other half comes from Northern California. But growing demand on both sources from other population centers and federal restrictions on the Colorado River threaten to leave San Diego dependent on water that is no longer available. That dire prospect, coupled with an ongoing drought in the early part of the last decade, spurred the water department, in 1994, to issue an open call for solutions to America's finest water conundrum. "We figured it was a good idea to put out a general request -- in city speak it is called an RFP, which is a request for proposals -- for ideas on how to move water into San Diego."

Specifically, the request was for a way to deliver 20,000 acre-feet of water -- enough for 40,000 households for a year -- by the year 2004, and to do it at a cost to the water department at or lower than $440 per acre-foot, the current rate they pay for water. "Since then, we've had lots of different ideas expressed to us," Kidman says. "We've had desalinization-technology ideas, we've had people who want to lay water lines along the ocean floor, we've had people who want to tow icebergs down here. We've had people who want to take old single-hull oil tankers and fill them with water and bring them down here. We always listen to these proposals, and we always work with the people up to a certain point because it would be irresponsible for us not to."

But none of those proposals has ever progressed past the idea stage. Now, a new idea has surfaced that shares something in common with all the others Kidman lists: getting the water here via the Pacific Ocean. An international consortium of companies has proposed transporting water from two Northern California Rivers to San Diego in polyfiber bags, 100 feet in diameter and over 800 feet long, towed behind oceangoing tugboats.

Four large companies compose the consortium known as World Water SA: Muzutech, a Saudi investment firm interested in developing technology; NYK Lines, a Japanese firm with the distinction of being the largest shipping company in the world; Nordic Water Supply, a Norwegian bulk shipping company already using water-transport bags to haul fresh water between Turkey and the island of Cyprus; and Alaska Water Exports. The last was founded by Ric Davidge, a former subcabinet member in the Reagan administration's Department of the Interior. He has also served as director of water and chief of hydrologic survey for the State of Alaska. Davidge is president of World Water SA. "I'm not a Johnny-come-lately to this business," Davidge says. "I've been studying the whole problem of water scarcity and the notion of transoceanic importation of water for well over ten years."

In the early 1990s, while water chief for the State of Alaska, Davidge "wrote a paper exploring all aspects of this industry, including the financial, ecological, international commerce, etc. I put that paper on the Internet, and it became sort of the seed that began a number of industries internationally looking at this concept. After I left the state, I was contacted by a number of companies from around the world to continue to work on this industry. And in 1999, World Water SA was formed, and I was asked to serve as president for the purpose of looking at specific possible projects."

He adds, "San Diego is one project I predicted in that paper would be one of the biggest and most important [oceanic water transportation] projects. It's not necessarily because the amount of water would be great (20,000 acre-feet is a lot of water, but in comparison with some other markets it is not) but because of its strategic location. And so when World Water SA was formed, we made a proposal to the City of San Diego saying we believed that we can adapt a bag technology, called water-transport bags, to deliver that amount."

Kidman says, of Davidge's proposal, "This is certainly the most serious attempt by somebody to find an alternate source of water in this way, absolutely. Now, with this technology, this gentleman has certainly created more of a stir and has certainly gotten further along than anybody else. Usually, what happens is we hear from somebody, we talk to him two or three times, and we don't hear from him again. But [Davidge] is making a sincere effort to make something work. He's asked us for materials, he's kept us updated on his process, and so we are working with him to a certain extent; if he needs information or something like that, we try to help him out. But he's got a tremendous amount of work to do on his end, before anything happens."

As with any water project, the first step was to decide where to collect or divert fresh water from its natural path to the Pacific Ocean. "We conducted an extensive study," Davidge explains, "on all the outflows in California, Oregon, and Washington, that we determined were environmentally developable and cost developable. After that we looked at things like upstream contamination with agriculture and industrial uses. We looked at historic flow rates both seasonally and annually. We looked at the cost of engineering to get the water from the little river to the bag offshore. We looked at saltwater intrusion distance; that is, how far upriver does the saltwater go when the tide is high and the [river] water is low, because obviously you can't take the water in that area because of the contamination of the saltwater."

Davidge and his engineers selected 15 sites, then narrowed that pool to five, then to a final two rivers, the Albion and Gualala Rivers, the former in Mendocino County, the latter in both Mendocino County and Sonoma County to the south. Both sites are over 100 miles north of San Francisco.

The next step was to figure out how to collect the water from the rivers. Davidge says his engineers have come up with a simple system that will have a minimum effect on the rivers. "It's not like what anyone else does," he explains. "Usually, when somebody harvests water out of a river, they put a pipeline in the river and they simply pump the water up into a water utility. That means the water downstream from that take point is lower as a result of that artificial impoundment or taking. So it clearly does have an effect on the downstream fish and wildlife and recreational uses and aesthetic concerns. What we want to do, what we proposed to the state, is to bury a concrete cistern into what we call the alluvial material, which is the sand and rock underneath the river. And we will run the pipeline within the rivers' hydrologic system. In other words, we don't take any water out of the riverbed, we don't displace any water out of the river, until the river dumps into the ocean. So although we are intercepting -- or what we call segregating -- the water upstream just above the highest point of saltwater intrusion the water is not being moved from the river's hydrologic system until it enters the ocean. So it has no effect on flow or water depth. And because we put this into the alluvial material, rather than just lay it in the river, we are not interfacing with fish and wildlife. It is aesthetically not visible; you can't see it. So, environmentally, we have designed a way to harvest water from streams that has no measurable downstream effect."

Davidge concedes that the river will be disturbed and the water dirtied during the laying of the pipeline. "So you do it in a single operation," he explains, "in which you dig and lay the pipe at the same time. You get that done quickly and get out of there and clean it up. But what you are doing there, particularly in these Northern California rivers, is nothing more than what happens during a storm surge. The amount of loading [that is, dirtying the water] that takes place in a storm surge, especially when you have significant 50-year [storms], is far more dramatic than what we would be involved with in burying the pipe."

A pump in the under-river cistern will maintain pressure in the line. The giant water-transfer bags in Davidge's plan will not be filled in the river. The pipeline running through the alluvial will continue out the mouth of the river to a buoy far enough out in the ocean to be beyond the surf. "The pipeline goes off into the ocean and runs out a distance to get away from the tidal area," Davidge explains. "We don't want to be interacting with waves and those kind of things. It ends at a buoy where the bag can be hooked up to it, and there is a pumping system underneath the buoy that is not visible from the shore. That pumps the water into the bag."

A similar pipeline and buoy system would need to be constructed here in San Diego to transfer water from the transport bags into our water system. As of yet, no potential site has been selected for that pipeline.

Davidge filed his application with the state in February. The state is now in a six-month period of public response to the proposal. Mendocino County's board of supervisors' response was to pass a resolution against the project. And in the rural towns of Albion and Gualala, near the mouths of the two rivers, there has been plenty of it. Each town has its own group in opposition, each with a catchy acronym of protest for a title. In Albion, it's FLOW (Forget Lifting Our Water) and in Gualala it's SORE (Save Our Rivers and Estuaries). Davidge calls these responses emotional and uninformed and points out a legal misconception imbedded in the very titles of the protest groups. "As the director of the state Water Resources Board told them in a meeting recently, 'It is not your water. That water belongs to the people of California.' "

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