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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,



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INFRASTRUCTURE RENEWAL 61 Using Water for Urban Renewal Daniel P. Loucks Cornell University ABSTRACT The needs for clean water in all aspects of urban development and mainte- nance can be met through the integration of multiple decentralized schemes for capturing and collecting precipitation, wastewater sanitation manage- ment, and modernization of infrastructure maintenance technologies. New York City has had success in using natural systems to provide clean drink- ing water and manage storm runoff. The city has saved billions of dollars through integration of diverse methods for controlling water quality, distri- bution, 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,

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er but also on the fact that there are no substitutes. (Even if we drank only beer, it is mostly water a es 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 compon wn in Figure 1 are impacted by each other, in part by how water is allocated to them and how clima 62 LIVABLE CITIES OF THE FUTURE ch seems to be changing, plays a role in determining the available supplies of water. FIGURE 1  Water is a critical input to all sectors of our economy and to our built and GURE 1 Water is a environments. to all sectors of our economy and to our built and natural natural critical input ironments. in part by how water is allocated to them and how climate, which seems to be But what is amazing, at least to me, is that everyone living on this planet could not only survive bu ve on the small percentage of roletotal freshwater the availableis actually available to use globally. H changing, plays a the in determining supply that supplies of water. ch is that? If a half-liter (oneamazing, at least to represents all the water onon this planet But what is pint) water bottle me, is that everyone living this planet, only a teaspoo hat water is available only survive but thrive on than what you can put the total fresh- could notfor human use. That is less the small percentage of in the cap of that bottle. Th uble is that this water is not always where and when use globally. How much quality If a water supply that is actually available to and of the quantity and is that? needed. And the metimes therehalf-liter (oneof it. Cities have to consider all the water on this planet, only a their is too much pint) water bottle represents both the reliability and quality of hwater supplies as well as protectionavailabletoo much ofuse. That is less than what you teaspoon of that water is against for human it in any given time period. Urban areas d stormwatercan put in the cap of that bottle. The trouble is that this water is not always management. where and when and of the quantity and quality needed. And then some- times 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

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Let’s focus on the water-urbanization link, highlighted in Figure 2. How do we provide the right ount of water at the right places, times, pressures, qualities, and costs? And how can water be used t ance the urban environment and aesthetics? After all, according to the New York Times (Oct. 7, 201 percent of all INFRASTRUCTURE RENEWAL areas. So this issue is important to most of us. Americans now live in urban 63 URE 2 The FIGURE 2  The Water-Urbanization Nexus Water-Urbanization Nexus ban Renewal: “Grey” versus “Green” Infrastructure an renewal is a primary approach to building new be improved given sufficient funding, industry, cities, the options or opportunities can infrastructure, attracting job-producing ilizing communities, governance, andresidents’ quality of life. It almost always involves investment effective and improving appropriate technical expertise. astructure. 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, y Infrastructure qualities, and costs? And how can water be used to enhance the urban envi- he past public works engineers had a majorall, according toonly New York Times (Oct. 7, ronment and aesthetics? After role, if not the the role, in the planning, design, elopment, installation, percent of all Americans now live in urban areas. So this issue is 2012), 80 and operation of water supply and stormwater management infrastructures. se engineers important to mostconcrete and steel, so they do, and the concrete and steel infrastructu are trained to use of us. y 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 plan URBAN RENEWAL: “GREY” VERSUS “GREEN” INFRASTRUCTURE then through storage and distribution systems to the tap. Wastewater systems typically pump tewater through collection sewers to wastewater treatment plants, and the resulting effluent may be Urban renewal is a primary approach to building new infrastructure, attract- sed or released into natural water bodies. Many creeks, streams, and rivers now flow through cities ing job-producing industry, stabilizing communities, and improving resi- erground in pipes and tunnels. Rainfall that used involvesinto the groundinfrastructure. runoff from dents’ quality of life. It almost always to soak investments in now becomes ed (impervious) areas and flows into cement ditches and stormwater drains, again becoming an erground waterway in either pipes or tunnels. All of this water is out of sight, out of mind, and efiting no one. Grey Infrastructure Reliable and safe water supply and sanitation systems are basic necessities of urban areas. In In the past public works engineers had a major role, if not the only role, in the eloping regions, however, they are not always available (Figure 3). Clean drinking water is still not planning, design, development, installation, and operation of water supply ilable to about a billion people—one out of seven. These people cannot be fully productive membe heir communitiesstormwater management infrastructures. These engineers in cities—lack adequate and or cities. Even more people—2.4 billion, most of them are trained to

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64 LIVABLE CITIES OF THE FUTURE 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 necessi- ties of urban areas. In developing regions, however, they are not always avail- able (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 oppor- tunity 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 recog- nized for successfully using natural systems to provide clean drinking water and manage stormwater. DEP estimates that such efforts have saved rate- payers 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/.

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

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66 LIVABLE CITIES OF THE FUTURE FIGURE 4  Green roofs are an increasingly widespread and effective way to reduce storm- water 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 bil- lion (NYCDEP 2012). New York City, like other older urban centers, is largely serviced by a combined sewer system in which stormwater and wastewater are trans- ported 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.

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INFRASTRUCTURE RENEWAL 67 Rather than build additional large storage tanks or tunnels to tempo- rarily 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 deten- tion 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 mea- sures 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 techni- cal capacity to do it and maintain it is often lacking. And the need is enor- mous. 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-

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68 LIVABLE CITIES OF THE FUTURE 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 envi- ronmental, 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.

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INFRASTRUCTURE RENEWAL 69 The value of these ecosystem services—such as pure water supply, and waste treatment and assimilation—needs to be factored into decision mak- ing 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 eco- nomic 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 gen- erally 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 conse- quences 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 pub- lic does not want to pay higher taxes that would enable the maintenance of water supply and wastewater collection and treatment infrastructure. As it

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70 LIVABLE CITIES OF THE FUTURE 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 high- lighted 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 sys- tems, increases in the costs of electricity, chemicals, and fuel used to supply 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.

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INFRASTRUCTURE RENEWAL 71 and treat water, compliance with federal government clean water mandates, rising pension and healthcare costs for water agency workers, increased secu- rity 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 infrastruc- ture 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 productiv- ity (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. Further- more, 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, recon- sideration 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?

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72 LIVABLE CITIES OF THE FUTURE 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 develop- ing 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 decentral- ized 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.