Water conservation usually isn't associated with the fight against global warming. But in truth, public agencies throughout California use huge amounts of electricity to move and pump water from the Sierra Nevada to points up and down the state. As a result, some environmentalists in recent years have argued that instead of burning fossil fuels to move water, we should take better advantage of local water resources, from capturing rainwater that lands on our rooftops to reusing so-called graywater to irrigate our gardens. In the East Bay, this idea appears to be catching on — quickly.
John Russell, who owns a small Oakland firm, WaterSprout, with his wife, Amy Schoneman, says the demand for rainwater and graywater systems has skyrocketed in the past year. Russell launched WaterSprout in 2006 after spending ten years in the landscaping business. "There's just been an explosion in demand for rainwater systems," he told Eco Watch during an interview in his North Oakland home. "And now I'm installing a graywater system every week."
Russell estimates that a graywater recycling system can save a typical family of four up to 30,000 gallons of water a year. "Graywater" refers to wastewater that comes from your bathroom sinks, shower, and washing machine, and can be used to irrigate your garden. The amount of water you'll save by installing a graywater system depends on the size of your garden and whether you plant native species or water-guzzling imports. Water from your kitchen sink, dishwasher, and toilet is considered "blackwater" because it can contain high levels of bacteria and thus cannot be safely reused in home-based treatment systems.
As for rainwater systems, they can save a typical family of four 12,000 to 16,000 gallons of water a year, Russell said. The captured rainwater provides all the water needed to flush your toilets and run your washing machine during California's rainy season — roughly from November through May or June, he said.
But as the popularity of rainwater catchment and graywater reuse systems has grown, so has the proliferation of illegal ones. Part of the problem is that California graywater regulations are unnecessarily strict. As a result, homeowners have purchased unlawful, unpermitted systems to avoid the onerous rules — or have decided not to install one at all. Russell estimates that 95 percent of graywater systems in California are illegal. So he and other environmentalists have been lobbying state regulators to greatly relax the rules in the hope that consumers will begin installing legal systems, and increase the growth of the industry overall.
WaterSprout sells two types of legal graywater systems that are eligible for permitting by local cities. The cheapest and simplest takes your home's graywater and pipes it directly to an underground irrigation system. WaterSprout sells this "gravity/branch drain" system for about $1,500. However, the water it generates can only can be used to irrigate high-water-consuming vegetation, such as fruit and bamboo trees, because the system does not filter graywater, Russell said. Consequently, it's unsuitable for lawns and most other types of plants and trees.
By contrast, the water from WaterSprout's sand-filter system can be used anywhere in your garden. The system pipes the graywater to an underground tank, and then pumps it through a sand filter and into an underground drip-irrigation system. It's also self-cleaning. Every two weeks, it sprays municipal water through the filter in the reverse direction, thereby dislodging built-up debris and sending it into the sewer line. As a result, you never have to change the filter. WaterSprout sells the system for $5,000 to $9,000, depending on the size of your house and garden, and the age and condition of your plumbing system.
Instead of a sand filter, WaterSprout also installs a graywater system that involves Russell building a mini-wetlands in your backyard. The wetlands naturally filter the graywater to an underground tank and then a pump sends the cleaned water to a drip-irrigation system. The wetlands system sells for the same price as the sand-filter system, but Russell said it is much harder to get permitted.
Among the California graywater rules that Russell and others want relaxed is the requirement that irrigation systems be buried at least twelve inches underground. The reason for the rule is that state officials don't want graywater pooling aboveground because of health concerns. But Russell and others argue that filtered graywater poses virtually no health risk, and by burying the irrigation so far underground, it actually inhibits the ability of nutrient-rich topsoil to filter the water more.
As for its rainwater catchment systems, WaterSprout diverts your home's downspouts to one or more large tanks, either above or below ground. Russell can also install soft-skin "pillow" tanks underneath your deck or home. To keep the water inside the tanks clean, Russell also installs filters on your rain gutters to keep out debris. Then, once the rainwater is in the tanks, it's pumped through additional filters and into your house to flush toilets and to run your washing machine. The rainwater system sells for $6,000 to $9,000, depending on the size and design. For more info, check out WaterSprout.org.
If the Fish Are Poisoned, What About the Water?
Last week, the California Water Resources Control Board released a scary report revealing that fish in most of the lakes and reservoirs throughout the state are contaminated with mercury, PCBs, and other toxins. The San Francisco Chronicle ran a front-page story on the report. But it left two unanswered questions: How bad are the fish in East Bay reservoirs, and if the fish are full of poisons, what about the water itself? That second question is particularly troubling, considering that many of the reservoirs in the study supply drinking water to California residents.
First, let's tackle the East Bay fish issue. According to Jay Davis, lead author of the study and toxicologist at the nonprofit San Francisco Estuary Institute in Oakland, fish that were caught in East Bay reservoirs were pretty contaminated. In both San Pablo Reservoir and Lake Chabot, large-mouth bass contained methyl mercury well above federal standards for human consumption. In other words, you shouldn't ever eat bass caught in those reservoirs. As for Briones Reservoir, the bass contained less methyl mercury, but still in concentrations that could cause health problems, particularly if you consume fish caught there more than three times a week.
And what about the water quality? Lake Chabot and San Pablo and Briones reservoirs are all owned and operated by the East Bay Municipal Water District, and they supply drinking water throughout the East Bay. So if the fish are contaminated, doesn't that mean the water is too? In short, the answer is no. Fish become contaminated because they're at the top of the water food chain. Methyl mercury tends to accumulate in algae, which then is passed up the chain to the large-mouth bass. However, that doesn't affect our drinking water, because East Bay MUD filters out the algae and other species before piping the water to our homes and businesses. In other words, drink the water, but don't eat the fish.