September 2008, Vol. 20, No.9


Truly Sustainable Water Infrastructure

It’s time to invest in next-generation decentralized technologies

Valerie I. Nelson

The debate about the recently enacted federal economic stimulus package has renewed discussion about whether the United States should be investing billions of dollars more to rebuild our aging infrastructure. Water lines, sewer mains, and treatment plants, many built more than 100 years ago, are leaking, collapsing, and overflowing. Utilities wanted federal money to help fix these problems, but pressure to slim down the package quieted that discussion temporarily.

Here’s another thought: Use the reality of deteriorated infrastructure as a rationale for investing in next-generation technologies and designs. There is a concept in asset management called “run to failure,” where it is efficient to stop repairing the old system and eventually to replace it with something new. Since much of our water and wastewater infrastructure seems to be well on its way to breaking, we have a golden opportunity to leapfrog into the future — as developing countries such as China and India are beginning to do. Calling our essential infrastructure’s failure an “opportunity” may seem counterintuitive, but if we had kept these systems in good shape, we actually would have fewer openings to shift to something new.

We all can find examples of running to failure in our own financial choices. Maybe we’ve let our old car get run down. We still change the oil regularly, and we keep the brakes working. Otherwise, we stop investing in the car and start to save every last dime for a new one — maybe a more efficient car this time, or a hybrid.

In the mid-1800s, we started piping clean water into cities and building drainage and sewer pipes to take away stormwater and wastewater. These systems have saved lives by reducing pathogen exposures and preventing periodic flooding.

But this big-pipe, centralized infrastructure is not sustainable over the long term. These municipal systems consume too much water, disrupt too many ecosystems, and use too much energy to move water and wastewater around. Growing populations, increasing land development, and climate change will make these problems much worse.

Next-generation designs come from a different engineering model: Use, treat, store, and reuse water efficiently on a smaller scale, and blend these designs into restorative water hydrologies. Some homeowners are already using water-efficient washing machines and recycling sink and shower water to irrigate lawns. Rain gardens and green roofs can collect stormwater and prevent flooding and sewer overflows. A new idea is to recapture energy and nutrients from wastewater.

In Seattle, Philadelphia, and Chicago, officials are designing water services in ways that also improve air quality, restore urban streams, and replace pavement with parks and urban gardens. Groups in Georgia and California are learning that more efficient next-generation systems that reuse water and replenish aquifers are critical for addressing deepening drought conditions. New subdivisions now can be built that need virtually no imported water.

New York City’s Battery Park City has several new high-rises that treat stormwater runoff and wastewater and recycle it back into landscaping, cooling towers, and toilet flushing. Officials are offering incentives for such approaches because they understand that each gallon of fresh water they don’t need to pipe in and each gallon of wastewater and stormwater they don’t have to pipe out reduces pressure on the city’s aging underground water and sewer systems.

It’s nice to see these scattered models in the United States, but other countries’ investments in next-generation approaches dwarf ours. Singapore and Abu Dhabi, as well as Shanghai, China, are devoting staggering amounts to research and demonstration projects for a sustainable water infrastructure, prompting U.S. companies and engineering firms to look abroad for the big next-generation markets.

Part of our problem is a legacy of well-intentioned rules and regulations, such as the Clean Water Act, which continue to support the use of wasteful and disruptive technology. Municipal utilities must comply with national permit requirements for old best practices that are costly and leave little room for creativity.

What will it take for our country to get on the path toward sustainable water infrastructure? For a start, we need to restore research funding so that we’re leading the development of new technologies and capturing jobs and profits in the global marketplace. We should provide tax incentives that encourage builders, architects, and homeowners to adopt and implement these systems. We need to rewrite federal legislation so that the best — not the most conventional — technologies can be used in our cities and towns.

As for the “sunk” costs of our aging infrastructure? We need to think seriously about how to shift our national investments toward the future. It is important to keep old pipes working well enough at critical points to protect public health. But instead of using federal funds to repair and replace these pipes and treatment plants in the old way, it may be wiser to pivot federal investments into the new.

Valerie I. Nelson is director of the Coalition for Alternative Wastewater Treatment (Gloucester, Mass.).