Can Earthworms Solve the Water Scarcity Problem?

Nature Can Clean Our Polluted Water Efficiently and Inexpensively

Many farms, especially dairy farms, struggle with how to dispose of polluted wastewater. The hundreds of millions of gallons of water farms use gets contaminated with animal waste, artificial fertilizers, and harmful chemicals, which frequently percolate down to the groundwater that people could one day drink.

Some regenerative ag operations are finding a nifty solution to this problem. They are discovering that earthworms, those ubiquitous dirt-eaters, are also able to clean water. They have long been known as nature’s way of enriching soil, but only recently has it been found that they can also cleanse wastewater. 

BioFiltro, an international company, has installed more than 200 of their three-stage wastewater treatment systems. The first chamber contains wood chips, earthworms, and microbes. The second level filters the water through crushed rock, and finally the cleaned water is collected in a drainage basin. A dairy farm in Washington State pumps half a million gallons of manure and chemical-laden water through a BioFiltro vermifiltration unit each day. The worms devour all the manure and harmful chemicals while aerating the water and wood chips. The aeration by the worms prevents the chip layer from clogging and becoming anaerobic. The density of worms is around 12,000-18,000 per cubic yard. The dairy reuses this treated water 10 times.

Vermifiltrated water is highly nutritive, pathogen-free, and scrubbed of chemicals, qualifying it for use on crop fields. The key to this low-cost, efficient, and odor-free process is the earthworm. These workers live, on average, six years, have numerous offspring, and each one produces about 10 pounds of castings per year, a nutritious and valuable soil amendment. This vermicompost can produce an additional income stream for farmers or can be used on their own crops.

Traditional wastewater treatment is energy-intensive and generates around 5 percent of all greenhouse-gas emissions (GHG). In comparison, vermifiltration requires almost no electricity, thereby reducing GHG emissions by 91 percent. Astoundingly, earthworms remove more than 80 percent of nitrites in wastewater and reduce methane emissions by an even higher percentage.

Vermifiltration was recently approved to become a component of the California Department of Food and Agriculture’s Alternative Manure Management Program — a program that provides funding to farmers who install sustainable GHG-reducing systems.

Water is becoming an increasingly valuable and scarce resource. Climate change and droughts are further taxing the planet’s limited supplies of fresh water; 85 percent of fresh water is used in global agriculture. Vermifiltration offers great hope for cleaning, reusing and stretching our supply of water. It has even proven to be effective in treating industrial and municipal wastewater. Some scientists believe it to be one of the most promising efforts to stem the global water crisis.

Eco-Friendly Cooling Equipment is Coming

Mechanical Cooling Needs to Use Less Energy and Avoid Dangerous Refrigerants

Heat waves are becoming more frequent, more extreme, and more widespread. Air-conditioning (AC) is ubiquitous in the U.S. (90 percent penetration), but not in Europe and many other regions where it is increasingly becoming a necessity. Outside the U.S., less than 25 percent of people in regions that merit AC have it. Consequently, the International Energy Agency expects AC energy consumption to triple worldwide by 2050.

Unfortunately, AC, in its current form, carries significant environmental costs: More demand for cooling leads to more warming of the planet. In addition, the refrigerants used in cooling condensers are 2,000-3,000 times more potent than carbon dioxide as a climate-warming agent when it leaks into the atmosphere.

Gradient Comfort, a San Francisco–based company, is tackling AC’s climate predicament — their mission is to push the industry to zero carbon emissions. Gradient has developed an innovative window cooling and heating unit that is both efficient and eco-friendly. It is a heat pump, a technology gaining in popularity for centralized heating and cooling systems because of energy efficiency, but such equipment tends to be bulky, expensive, and requires professionals to install. Gradient’s technology, however, offers a sleek, affordable, and compact alternative. 

The only Gradient model currently available (it only came on the market this summer) is a window unit. It sells for $2,000 compared to $5,000 or more for comparable units. Their saddle bracket fits on the windowsill of a single- or double-hung window and holds a sleek, attractive fan-coil unit on the inside while the evaporator heat pump is on the outside. Both components fit below the window, so that views are not obstructed. Housed with the fan coil is a quiet fan, eliminating any noise issues. The company is designing other models to fit other styles of windows, e.g., casement units. The unit is planned for do-it-yourself installation in 15 minutes with just a few basic tools. 

Gradient won the Fast Company’s 2022 World-Changing Ideas Award. The cooling component is 30 percent more efficient than traditional window units. When both heating and cooling are combined, the improved efficiency jumps to 75 percent. Another big plus is the refrigerant: Although still a hydrofluorocarbon, the fluid used by Gradient has a quarter the global warming potential of those used by other AC manufactures. They are working to improve their refrigerant even more.

The Gradient device is designed to use only the amount of energy required as it is turned up or down. It is also linked to Wi-Fi in order that it can be self-adjusted when there is heavy demand on the electric grid.

Although Gradient needs more improvements to reach its goal of zero greenhouse-gas emissions, it has taken big first steps in addressing the widespread flaws in existing systems: high cost, cumbersome installations, and unsightliness. These are important directions for widespread adoption of cooling including in less affluent areas of the world.

The Lompoc Strauss Wind Farm

Santa Barbara Is Well on the Way to 100 Percent Renewable Electricity

A small group of us had the privilege of recently touring the Strauss Wind Energy Project in Lompoc while it is under construction. It is the first and only wind project permitted anywhere along the California coast. From the first earlier permitted version of 65 generators, it has been scaled back to 27 machines, yet with the capacity to produce 100 megawatts of electricity.

Reducing the number of turbines has significant environmental and economic benefits. Major advances in “wind” technology during the past 10-15 years have boosted the output possible for a single generator. Each Strauss platform is rated at 3.8 megawatts, the largest land-based turbine available in the U.S. Blades are 227 feet long, the towers 492 feet tall. Scheduled completion date is December this year. Once operational, project will produce the electricity to power 45 thousand houses. For the next 30 years, it will keep six million metric tons of CO2 from entering the atmosphere and warming the planet. This is the equivalent of not driving 16 billion miles. In addition, it will infuse $40 million into Santa Barbara’s tax coffers.

The next wind project along the California coast will likely be offshore, either in the ocean off Morro Bay or off the coast of Humboldt. Both zones have received federal and state approval and are being readied for bulk permitting. The Biden administration recently approved a Massachusetts plan for the nation’s first commercial-scale offshore wind farm. A dozen other East Coast offshore wind projects are now under federal review. Unlike the East Coast, California faces the logistical challenges posed by a deep ocean floor. Evolving technologies, developed mostly in Europe, now make wind generators on floating platforms feasible, as well as even larger ones than land-based units. There is a wind farm with 6-megawatt turbines operating in the North Sea. There is also a 14-megawatt turbine that has been successfully producing for two years in Rotterdam Port.

Santa Barbara has set a goal of 100 percent renewable electricity by 2030. The adoption of community choice energy programs in the Tri-Counties, an initiative advocated and led by the Community Environmental Council, now has 1.4 million households getting at least 50 percent of their electricity from renewables, and many as much as 100 percent. All will be getting to the 100 percent goal by the end of this decade. The Strauss wind farm, when it comes online, will be a big component of local clean energy production.

Wind energy is an ideal complement to solar energy because winds tend to be strongest in the evening and at night. The distributed photovoltaic panels on buildings throughout the County together with the 40-megawatt Cuyama solar farm and the 100-megawatt Strauss wind farm will produce about two-thirds of the electricity Santa Barbara consumes. The county is well on the way to meeting its 2030 goal.

Floodplain Restoration

In Response to Climate Change, California Is Looking to Nature’s Patterns

Water policy in the Western U.S. has always been a contentious issue. Changes in water management, however, are slowly happening. For example, an increasing number of dams are being deconstructed where environmental, safety, and Indigenous-cultural impacts outweigh the benefits of hydropower, flood control, irrigation, or recreation. Dams across the U.S. have an average age of more than half a century, and many pose a growing safety risk. Power production from dams is becoming less economically viable as costs of solar- and wind-generated electricity fall. 

More recently, the issues of water wastage and flood control from dam removal are being offset by allowing rivers to return to more natural flow patterns. Floodplain restoration is occurring along the Mississippi River and in Washington State, but California is rethinking how rivers flow even more broadly and leads with an additional emphasis on ecological health as climate change alters the environment. Carefully selected types of woody trees and shrubs are being planted in restored floodplains to enhance wildlife habitat and attract native species. 

California’s largest floodplain restoration project, the 2,100-acre Dos Rios Ranch Preserve in the Central Valley (at the confluence of the Tuolumne and San Joaquin rivers), is removing levees so that when heavy rains occur, the rivers can overflow their banks and revert to their historic floodplains.

The state is prioritizing these types of projects to lower risks to homes and property while boosting wildlife habitat, improving water quality, and potentially recharging groundwater supplies. As climate change leads to higher temperatures, mountain snowpack that typically trickles into the watershed will likely increase river flows and flooding. The growing risk to cities like Sacramento and Stockton, both built in floodplains, is alarming experts. Not only are California’s dry periods getting drier, but scientists are expecting wet periods to get wetter.

The update to the Central Valley Flood Protection Plan, just being released, puts a premium on floodplain restoration to reduce risk to 1.3 million people who live in floodplains. Unlike in the contentious world of most California water policy, there is wide agreement on the value of restoring floodplains, which can also reduce one concern attached to dam removal projects. There is good funding news: The Biden infrastructure bill earmarks $1.75 billion for projects designed to reduce flood risk.

California officials initiated Central Valley flood planning only a decade ago, but in this short time have established the state as a leader, if not the leader. Since the 1850s, 95 percent of Central Valley wetlands and river habitats have been lost. Restoring all of that will be impossible, but the state is starting to reclaim some of these losses.