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Livable Cities of the Future: Proceedings of a Symposium Honoring the Legacy of George Bugliarello (2014)

Chapter: Using Water for Urban Renewal--Daniel P. Loucks

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Suggested Citation:"Using Water for Urban Renewal--Daniel P. Loucks." National Academy of Engineering. 2014. Livable Cities of the Future: Proceedings of a Symposium Honoring the Legacy of George Bugliarello. Washington, DC: The National Academies Press. doi: 10.17226/18671.
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Using Water for Urban Renewal

Daniel P. Loucks

Cornell University

ABSTRACT

The needs for clean water in all aspects of urban development and maintenance can be met through the integration of multiple decentralized schemes for capturing and collecting precipitation, wastewater sanitation management, and modernization of infrastructure maintenance technologies. New York City has had success in using natural systems to provide clean drinking water and manage storm runoff. The city has saved billions of dollars through integration of diverse methods for controlling water quality, distribution, use, and reuse.

URBAN WATER IN THE LARGER WATER NEXUS

Humans depend on water for life, which is obvious, but also for almost everything we see or make. Everything you see while reading this document required water to create, including the electricity and bulbs that provide the light you may be seeing it with. Humans are completely dependent not only on water but also on the fact that there are no substitutes. (Even if we drank only beer, it is mostly water and takes a lot more water to make whatever amount of beer we drink.)

Water is a critical input to all sectors of our economy and environment (Figure 1). All the components shown in Figure 1 are impacted by each other,

Suggested Citation:"Using Water for Urban Renewal--Daniel P. Loucks." National Academy of Engineering. 2014. Livable Cities of the Future: Proceedings of a Symposium Honoring the Legacy of George Bugliarello. Washington, DC: The National Academies Press. doi: 10.17226/18671.
×

image

FIGURE 1 Water is a critical input to all sectors of our economy and to our built and natural environments.

in part by how water is allocated to them and how climate, which seems to be changing, plays a role in determining the available supplies of water.

But what is amazing, at least to me, is that everyone living on this planet could not only survive but thrive on the small percentage of the total freshwater supply that is actually available to use globally. How much is that? If a half-liter (one pint) water bottle represents all the water on this planet, only a teaspoon of that water is available for human use. That is less than what you can put in the cap of that bottle. The trouble is that this water is not always where and when and of the quantity and quality needed. And then sometimes there is too much of it. Cities have to consider both the reliability and quality of their freshwater supplies as well as protection against too much of it in any given time period. Urban areas need stormwater management.

A region’s demands for fresh water are a function of the need to provide clean drinking water and sanitation, to ensure public health in growing urban centers, to create electric and liquid fuel energy, to maintain a healthy environment and well-functioning ecosystems, to grow and process food, and to support the industries and economic development that provide jobs and welfare.

In developing regions meeting these needs is even more urgent, and often more difficult, especially in urban slum environments. But even in such

Suggested Citation:"Using Water for Urban Renewal--Daniel P. Loucks." National Academy of Engineering. 2014. Livable Cities of the Future: Proceedings of a Symposium Honoring the Legacy of George Bugliarello. Washington, DC: The National Academies Press. doi: 10.17226/18671.
×

image

FIGURE 2 The Water-Urbanization Nexus

cities, the options or opportunities can be improved given sufficient funding, effective governance, and appropriate technical expertise.

Let’s focus on the water-urbanization link, highlighted in Figure 2. How do we provide the right amount of water at the right places, times, pressures, qualities, and costs? And how can water be used to enhance the urban environment and aesthetics? After all, according to the New York Times (Oct. 7, 2012), 80 percent of all Americans now live in urban areas. So this issue is important to most of us.

URBAN RENEWAL: “GREY” VERSUS “GREEN” INFRASTRUCTURE

Urban renewal is a primary approach to building new infrastructure, attracting job-producing industry, stabilizing communities, and improving residents’ quality of life. It almost always involves investments in infrastructure.

Grey Infrastructure

In the past public works engineers had a major role, if not the only role, in the planning, design, development, installation, and operation of water supply and stormwater management infrastructures. These engineers are trained to

Suggested Citation:"Using Water for Urban Renewal--Daniel P. Loucks." National Academy of Engineering. 2014. Livable Cities of the Future: Proceedings of a Symposium Honoring the Legacy of George Bugliarello. Washington, DC: The National Academies Press. doi: 10.17226/18671.
×

use concrete and steel, so they do, and the concrete and steel infrastructure they build is called “hard” or “grey” (because of its color) construction.

Water supply systems typically pump natural water through pipes or canals to water treatment plants and then through storage and distribution systems to the tap. Wastewater systems typically pump wastewater through collection sewers to wastewater treatment plants, and the resulting effluent may be reused or released into natural water bodies. Many creeks, streams, and rivers now flow through cities underground in pipes and tunnels. Rainfall that used to soak into the ground now becomes runoff from paved (impervious) areas and flows into cement ditches and stormwater drains, again becoming an underground waterway in either pipes or tunnels. All of this water is out of sight, out of mind, and benefiting no one.

Reliable and safe water supply and sanitation systems are basic necessities of urban areas. In developing regions, however, they are not always available (Figure 3). Clean drinking water is still not available to about a billion people—one out of seven. These people cannot be fully productive members of their communities or cities. Even more people—2.4 billion, most of them in cities—lack adequate sanitation. The World Health Organization (WHO) reports that 3.4 million of these people die each year, about the population of the city of Los Angeles.1

New York City certainly does not have the water supply and sanitation issues that developing regions have. But it does have an infrastructure that requires attention. The 15- to 35-million-gallon daily leak in the Delaware Aqueduct may be among the most visible evidence of this, except for the street where a water main breaks and half the street instantly disappears.

Here and in cities around the country and the world, there is an opportunity to manage stormwater runoff in more energy- and cost-efficient ways that will also enhance the environment of those who live and work in the city.

Green Infrastructure

The NYC Department of Environmental Protection (DEP) is widely recognized for successfully using natural systems to provide clean drinking water and manage stormwater. DEP estimates that such efforts have saved ratepayers billions of dollars—by eliminating the need for construction of hard infrastructure such as storm sewers and filtration plants—while preserving large tracts of natural areas. The department’s Green Infrastructure Plan lays

___________________

1 The WHO data are available online at www.who.int/water_sanitation_health/hygiene/en/.

Suggested Citation:"Using Water for Urban Renewal--Daniel P. Loucks." National Academy of Engineering. 2014. Livable Cities of the Future: Proceedings of a Symposium Honoring the Legacy of George Bugliarello. Washington, DC: The National Academies Press. doi: 10.17226/18671.
×

image

FIGURE 3 There are stark differences in the availability of sanitary facilities between developed and developing countries. Reprinted from Grayman et al. (2012) with permission from ASCE.

Suggested Citation:"Using Water for Urban Renewal--Daniel P. Loucks." National Academy of Engineering. 2014. Livable Cities of the Future: Proceedings of a Symposium Honoring the Legacy of George Bugliarello. Washington, DC: The National Academies Press. doi: 10.17226/18671.
×

image

FIGURE 4 Green roofs are an increasingly widespread and effective way to reduce stormwater runoff. Reprinted from Grayman et al. (2012) with permission from ASCE.

out how the city will improve the water quality in New York Harbor, for example, by capturing and retaining stormwater runoff before it enters the sewer system, and from there the harbor, through the use of streetside swales, tree pits, and blue and green rooftop detention techniques to absorb and retain stormwater (Figure 4). This hybrid approach will reduce combined sewer overflows by 12 billion gallons a year—over 2 billion gallons a year more than the current all-grey strategy—while saving New Yorkers $2.4 billion (NYCDEP 2012).

New York City, like other older urban centers, is largely serviced by a combined sewer system in which stormwater and wastewater are transported together through a single pipe. Treatment plants are designed to treat and disinfect twice the dry-weather flow, but during heavy storms the system can exceed its capacity. When this happens a mix of stormwater and wastewater—called combined sewer overflow (CSO)—is discharged into New York Harbor. DEP has committed to reducing the annual volume of CSOs by more than 8 billion gallons over the next 20 years—10 percent of the runoff from the city’s impervious surfaces.

Suggested Citation:"Using Water for Urban Renewal--Daniel P. Loucks." National Academy of Engineering. 2014. Livable Cities of the Future: Proceedings of a Symposium Honoring the Legacy of George Bugliarello. Washington, DC: The National Academies Press. doi: 10.17226/18671.
×

Rather than build additional large storage tanks or tunnels to temporarily store stormwater at the end of the sewer system, DEP determined that it was more cost effective to first construct source controls and “soft” infrastructure (e.g., bioswales, blue and green roofs, and subsurface detention systems) to control and reduce stormwater runoff from impervious spaces such as roofs, sidewalks, and parking lots. Together with conservation measures and operational improvements, the widespread adoption of such soft infrastructure can reduce CSOs at less cost than second-tier hard or grey infrastructure. Moreover, green infrastructure provides many quality of life benefits, by improving air quality, increasing shading, contributing to higher property values, and enhancing streetscapes.

The department is also implementing lots of other innovative measures such as giving people rain barrels, installing automated meter-reading devices, and developing an energy strategy that will (1) reduce the carbon footprint, including emissions of greenhouse gases; (2) reduce electricity demand, the cost of which is expected to almost double every 5 years in the absence of aggressive energy efficiency investments; and (3) explore clean energy options.

WHAT HAVE WE LEARNED?

Experience indicates that green buildings can reduce energy costs, water use, and carbon emissions by 30–50 percent. In addition, going green can create environments that attract people rather than motivate them to leave. Living and working in a greener, more natural environment can quite literally make people feel better.

But in the developing world, providing adequate water supplies and sanitation in expanding urban areas is tough. It would be a challenge even if water supplies were adequate and funding were available, because the technical capacity to do it and maintain it is often lacking. And the need is enormous. As mentioned above, the equivalent of Los Angeles’ population dies every day from diseases associated with dirty water, and the risks are greatest for children. It’s an economic issue in the affected regions, and a moral issue for all of us more fortunate thanks simply to the luck of the draw. It’s a major issue on the agenda of many UN and relief agencies today.

Here in New York City the issues are how to revitalize urban areas and manage stormwater runoff in ways that contribute to the revitalization of neighborhoods and at the same time save money. We are learning that we can do it through the construction and adoption of blue and green roofs, street-

Suggested Citation:"Using Water for Urban Renewal--Daniel P. Loucks." National Academy of Engineering. 2014. Livable Cities of the Future: Proceedings of a Symposium Honoring the Legacy of George Bugliarello. Washington, DC: The National Academies Press. doi: 10.17226/18671.
×

side bioswales, tree pits, and other green infrastructure that absorbs or delays runoff from storms, keeps it out of combined sewer systems, and reduces CSOs, which are the primary source of pathogens in New York Harbor. We have learned that we can save billions of dollars by not having to build as much hard infrastructure for stormwater runoff, and at the same time we can beautify neighborhoods, increase property values, and improve air quality.

GOVERNANCE CHALLENGES

But there are challenges relevant to implementing effective water–urban renewal projects. Experiences in New York City and elsewhere in the United States and abroad suggest that work is still needed to address:

1.   the often fragmented nature of water systems management and the lack of a clear central government “home” for the necessary policy and legislation that underpin this essential resource and its infrastructure;

2.   the lack of sufficient stakeholder awareness and understanding of urban water systems and involvement in their management—reaching a consensus among the various stakeholders on the environmental, social, and economic goals of urban water systems takes time, and time is money;

3.   the need for a better understanding of the issues among all stakeholders;

4.   community and political tensions surrounding water businesses: who owns water, who manages it, and how it is valued and priced;

5.   concerns about equitable access to water and privatization of water systems;

6.   the lack of appreciation of the need to manage water in an integrated way according to ecosystem principles;

7.   the disaggregated view of urban water management needs, which is shaped by current infrastructure models and is a major barrier to developing more sustainable, fully integrated, and cost-effective systems—a more integrated, lifecycle approach is required, treating the various components of water catchment, supply, wastewater, and stormwater as one system or life cycle, and in turn supporting the renewal of other urban service systems; and

8.   the lack of recognition and understanding of the role of ecosystem services, and a resultant undervaluing of the associated benefits of these services.

Suggested Citation:"Using Water for Urban Renewal--Daniel P. Loucks." National Academy of Engineering. 2014. Livable Cities of the Future: Proceedings of a Symposium Honoring the Legacy of George Bugliarello. Washington, DC: The National Academies Press. doi: 10.17226/18671.
×

The value of these ecosystem services—such as pure water supply, and waste treatment and assimilation—needs to be factored into decision making and incorporated into asset management planning.

No doubt there are other needs and challenges in specific cities, but in each case it is fair to say that enhancing water management along with urban renewal is primarily a sociopolitical challenge rather than an economic or technical one. Certainly capital constraints and some technical issues can restrict opportunities. But it is the way institutions are organized and function—the legislation, policies, infrastructure, and community expectations—that is the greatest challenge, in my opinion.

While the water–urban renewal nexus challenges mentioned above generally apply globally, decisions about water management and urban renewal are made at the regional or local level. Water is linked to local politics and without adequate governance—a decision-making process often requiring reforms in many political and social systems—progress in integrating water in urban renewal will be limited.

Governance is not made any easier when those who benefit from the allocation and use of water cannot know of the tradeoffs made elsewhere to provide that water and the costs or damages to others as a consequence of allocation decisions. This has to do with economic globalization that decouples the risks and costs to some and the rewards and benefits to others at a distant location. The inability to observe or even be aware of the consequences of our decisions has implications for progress toward achieving a more sustainable environment and socioeconomic development.

All this argues for a more decentralized approach.

VALUING, PRICING, AND CHARGING FOR WATER SERVICES

Although New York City has some of the best-tasting and safest water in the world, many New Yorkers studiously avoid drinking it. Instead of giving the public water supply the respect it deserves, they purchase 1.25 billion plastic water bottles every year, requiring 60 million gallons of oil to produce and costing the city approximately $8 million annually to dispose of them. The average recycling rate of these plastic bottles is only 25 percent, which means that 75 percent end up either in a landfill or in the ocean.

What is also interesting, at least to me, is the fact that the public still expects water to be, if not free, a low-cost good. Surveys show that the public does not want to pay higher taxes that would enable the maintenance of water supply and wastewater collection and treatment infrastructure. As it

Suggested Citation:"Using Water for Urban Renewal--Daniel P. Loucks." National Academy of Engineering. 2014. Livable Cities of the Future: Proceedings of a Symposium Honoring the Legacy of George Bugliarello. Washington, DC: The National Academies Press. doi: 10.17226/18671.
×

is they end up paying higher water utility bills, or higher taxes that are not identified or related to water services. But without adequate funding for maintenance the likely result is periodic emergency repair of broken water pipes or sewers. This in turn has motivated the development of “smart pipes” that can repair themselves without having to be dug up (Figure 5).

A USA Today (Sept. 28, 2012) article on the nation’s water costs highlighted the fact that some cities have experienced a doubling or tripling of costs over the past 12 years; for example, Atlanta, 223 percent; San Francisco, 211 percent; Wilmington, Del., 200 percent; Philadelphia, 164 percent; Portland, Ore., 161 percent; and New York City, 151 percent. The trend toward higher water bills is being driven by the cost of paying off the debt on bonds issued to fund expensive repairs or upgrades on aging water systems, increases in the costs of electricity, chemicals, and fuel used to supply

image

FIGURE 5 Smart pipes that can repair themselves reduce leaks without having to be dug up. Reprinted from Grayman et al. (2012) with permission from ASCE.

Suggested Citation:"Using Water for Urban Renewal--Daniel P. Loucks." National Academy of Engineering. 2014. Livable Cities of the Future: Proceedings of a Symposium Honoring the Legacy of George Bugliarello. Washington, DC: The National Academies Press. doi: 10.17226/18671.
×

and treat water, compliance with federal government clean water mandates, rising pension and healthcare costs for water agency workers, increased security safeguards for water systems since the 9/11 terror attacks, and a general decline in public water consumption.

CHALLENGES OF THE FUTURE

Urban populations are projected to rise, nearly doubling from the current 3.4 billion to 6.4 billion by 2050, with the number of people living in slums rising even faster, from 1.0 to 1.4 billion in just a decade. Already, half of the world’s population lives in cities, and 80 percent of Americans do.

Providing adequate water supply and sanitation, particularly in urban areas, is a challenging task for governments throughout the world. Many, especially in Africa and Asia, have virtually no or only inadequate infrastructure and limited resources to address water and wastewater management in an efficient and sustainable way. Because of inadequate infrastructure almost 85 percent of all wastewater is discharged to water bodies without treatment, resulting in one of the greatest health challenges, restricting development, and increasing poverty through costs to health care and lost labor productivity (UN 2012).

This task is made even more difficult by predicted climate changes, which are associated with significant alterations in precipitation patterns, both spatially and temporally, affecting the availability and variability of water supplies.

In addition, technological and financial constraints are challenges in maintaining and upgrading infrastructure assets to deliver water to all sectors while maintaining the quality of water distributed to various users. Furthermore, population growth, urbanization, and industrial activities are leading to a dramatic increase in water use and wastewater discharge.

Cities are facing difficult strategic decisions. Do they continue business as usual, following a conventional technical, institutional, and economic approach to water and sanitation? Do they tinker, following the conventional approaches while trying to optimize and fine-tune them? Or do they look for a new paradigm that considers interventions over the entire urban water cycle to provide security through diversification of water sources, reconsideration of the ways water is used (and reused), wastewater as a valuable resource, governance structures covering the entire urban water cycle, and the resiliency of water and sanitation to global change pressures?

Suggested Citation:"Using Water for Urban Renewal--Daniel P. Loucks." National Academy of Engineering. 2014. Livable Cities of the Future: Proceedings of a Symposium Honoring the Legacy of George Bugliarello. Washington, DC: The National Academies Press. doi: 10.17226/18671.
×

CLOSING REMARKS

To meet future urban water and sanitation challenges we have to rethink the way we manage urban water systems. We need a paradigm shift. A more integrated approach may transform threats into opportunities and address the challenges of urban water management in both developed and developing countries. Do we continue to spend money to treat water to drinking water quality only to use it to fight fires or carry wastes to a wastewater treatment plant? Do we continue to spend money on the traditional (grey) infrastructure?

In addition to the integrated approach, do we consider more decentralized approaches where beneficial? Water reuse, energy recovery, the use of local water sources, and waterless toilets all foster decentralization. I predict that we will see many more integrated decentralized approaches to urban renewal efforts in the future, in the cities of both developing and developed countries.

REFERENCES

Grayman WM, Loucks DP, Saito L, eds. 2012. Toward a Sustainable Water Future: Visions for 2050. Reston, VA: ASCE Press.

NYCDEP [New York City Department of Environmental Protection]. 2012. NYC Green Infrastructure: 2012 Annual Report. Available at www.nyc.gov/html/dep/pdf/green_infrastructure/gi_annual_report_2013.pdf.

UN [United Nations]. 2012. World Water Development Report No. 4. Paris: World Water Assessment Program, UNESCO.

Suggested Citation:"Using Water for Urban Renewal--Daniel P. Loucks." National Academy of Engineering. 2014. Livable Cities of the Future: Proceedings of a Symposium Honoring the Legacy of George Bugliarello. Washington, DC: The National Academies Press. doi: 10.17226/18671.
×
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Suggested Citation:"Using Water for Urban Renewal--Daniel P. Loucks." National Academy of Engineering. 2014. Livable Cities of the Future: Proceedings of a Symposium Honoring the Legacy of George Bugliarello. Washington, DC: The National Academies Press. doi: 10.17226/18671.
×
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Suggested Citation:"Using Water for Urban Renewal--Daniel P. Loucks." National Academy of Engineering. 2014. Livable Cities of the Future: Proceedings of a Symposium Honoring the Legacy of George Bugliarello. Washington, DC: The National Academies Press. doi: 10.17226/18671.
×
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Suggested Citation:"Using Water for Urban Renewal--Daniel P. Loucks." National Academy of Engineering. 2014. Livable Cities of the Future: Proceedings of a Symposium Honoring the Legacy of George Bugliarello. Washington, DC: The National Academies Press. doi: 10.17226/18671.
×
Page 64
Suggested Citation:"Using Water for Urban Renewal--Daniel P. Loucks." National Academy of Engineering. 2014. Livable Cities of the Future: Proceedings of a Symposium Honoring the Legacy of George Bugliarello. Washington, DC: The National Academies Press. doi: 10.17226/18671.
×
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Suggested Citation:"Using Water for Urban Renewal--Daniel P. Loucks." National Academy of Engineering. 2014. Livable Cities of the Future: Proceedings of a Symposium Honoring the Legacy of George Bugliarello. Washington, DC: The National Academies Press. doi: 10.17226/18671.
×
Page 66
Suggested Citation:"Using Water for Urban Renewal--Daniel P. Loucks." National Academy of Engineering. 2014. Livable Cities of the Future: Proceedings of a Symposium Honoring the Legacy of George Bugliarello. Washington, DC: The National Academies Press. doi: 10.17226/18671.
×
Page 67
Suggested Citation:"Using Water for Urban Renewal--Daniel P. Loucks." National Academy of Engineering. 2014. Livable Cities of the Future: Proceedings of a Symposium Honoring the Legacy of George Bugliarello. Washington, DC: The National Academies Press. doi: 10.17226/18671.
×
Page 68
Suggested Citation:"Using Water for Urban Renewal--Daniel P. Loucks." National Academy of Engineering. 2014. Livable Cities of the Future: Proceedings of a Symposium Honoring the Legacy of George Bugliarello. Washington, DC: The National Academies Press. doi: 10.17226/18671.
×
Page 69
Suggested Citation:"Using Water for Urban Renewal--Daniel P. Loucks." National Academy of Engineering. 2014. Livable Cities of the Future: Proceedings of a Symposium Honoring the Legacy of George Bugliarello. Washington, DC: The National Academies Press. doi: 10.17226/18671.
×
Page 70
Suggested Citation:"Using Water for Urban Renewal--Daniel P. Loucks." National Academy of Engineering. 2014. Livable Cities of the Future: Proceedings of a Symposium Honoring the Legacy of George Bugliarello. Washington, DC: The National Academies Press. doi: 10.17226/18671.
×
Page 71
Suggested Citation:"Using Water for Urban Renewal--Daniel P. Loucks." National Academy of Engineering. 2014. Livable Cities of the Future: Proceedings of a Symposium Honoring the Legacy of George Bugliarello. Washington, DC: The National Academies Press. doi: 10.17226/18671.
×
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At the beginning of the 20th century an estimated five percent of the world's population lived in cities. Today, half the world's population is urbanized. Urban sustainability is multifaceted and encompasses security, economics, environment and resources, health, and quality of life. It can be viewed as the intersection of two extremely complex and not yet fully understood processes, urbanization and global sustainability, which will increasingly overlap as urban populations continue to grow. Effective policies are critical for addressing urban sustainability, and must be politically realistic in deciding on appropriate balances, such as centralized versus decentralized systems, "soft" versus "hard" solutions, local versus regional focus, agriculture versus pollution, and free markets versus interventions.

Livable Cities of the Future, a symposium honoring the legacy of George Bugliarello, was hosted October 26, 2012, by the Polytechnic Institute of New York University (NYU-Poly) in the Pfizer Auditorium of the Bern Dibner Library of Science and Technology. The event brought together more than 200 engineers, civic leaders, educators, and futurists to discuss how George Bugliarello's vision manifests itself in innovative urban planning for the cities of tomorrow. This report is a summary of the presentations and discussion at that event.

The symposium objectives were to cultivate ideas for best practices and innovative strategies for sustainable urban development and to facilitate the evolution of New York City to a real-life laboratory for urban innovation. Participants heard the perspectives and experiences of representatives from private and public service operators, infrastructure agencies, and the academic community. Elected officials and other stakeholders in urban and other sectors examined issues critical to resilient and sustainable cities, such as energy, water supply and treatment, public health, security infrastructure, transportation, telecommunications, and environmental protection.

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