Cities that carefully and creatively use their water assets for strategic urban advantage will ultimately be more livable, safe, and competitive. The cities that best understand this and act first will be the ones that not only avoid water crisis, but also will be the first to attract investment and improve their competitive position.
Water demand issues and climate change risks affect communities of all sizes every day, especially like we’ve seen in Houston this past spring and around Baton Rouge, La., this summer. Meanwhile, citizens continue to look to their city leaders to develop strategies, policies, and infrastructure to deliver water, sanitation, and resilience.
The U.S. offers several examples of urban water strategies that are sustainably improving quality of life. The first Arcadis Sustainable Cities Water Index ranks cities in the U.S. and around the globe on their water resiliency, efficiency, and quality (see Figure 1). The list of water-related challenges highlights the complexity of the problems that city planners and water authorities face. From these cities, we can also see what ideas are effective or worthy of more exploration.
Overall, most U.S. cities studied ranked well for water quality, with Chicago, Philadelphia, Boston, New York City, and Houston rising to the top 10. Many cities also have developed efficiency, water reuse, and asset management strategies to make sure their water systems meet demands.
On the other hand, the majority of U.S. cities struggle to achieve resilience to flooding and to prevent water scarcity, with most falling to the bottom half of the charts. As a result, despite high scores for water quality and water efficiency, no U.S. cities made the top 10 in the water sustainability rankings.
Water challenges worldwide
All cities face water challenges they are not fully equipped to address, from urbanization to climate change and aging infrastructure to water security. Left unaddressed, these challenges can become serious crises that can hold back growth or drain resources for years. These include the following:
Urbanization or population decline — Some cities are growing so fast that it can be hard for water systems built for smaller needs to meet levels of service. On the other hand, shrinking cities like those in the rust belt experiencing a 50 percent decline in population face a revenue shortage that can make it difficult to maintain large systems.
Water scarcity — Limited access to clean and safe water resources can lead to food shortages, economic slowdown, and even political conflicts that can further exacerbate the economic and competitive position of the affected city. Water scarcity is a growing problem in cities with vulnerable climates, limited natural water resources, and growing demand.
However, persistent drought is proving to be the mother of water efficiency in the west. For example, Los Angeles, which ranks #27 out of 50 cities globally for sustainability, is #2 in the world in water efficiency thanks to recent improvements and water reuse achievements.
Los Angeles is responding to its challenges in the short and long term, starting with the gubernatorial-mandated 25 percent water use reduction and earthquake preparedness initiatives. The city has also adopted the One Water LA plan, which will set the bar for a more sustainable and resilient way to manage the city’s future water needs through a collaborative approach yielding sustainable, long-term water supplies for Los Angeles in addition to greater resiliency to drought conditions and climate change.
Water excess and flooding — At the other end of the spectrum, cities can struggle with too much water. Suffering during heavy rainfall, like parts of the southern U.S. did this year, many cities lack enough green space and other stormwater strategies to buffer heavy rains, while coastal areas are hindered by sea level rise and storm surge.
Water quality is New York City’s outstanding strength, built on a program to reduce nitrogen and water pollution, extensive pretreatment, and reduced combined sewer overflows. Even still, New York ranked #14 out of 50 cities globally in the index for water sustainability. This low ranking for such an iconic city stems from, in part, events such as Superstorm Sandy, which revealed New York City’s vulnerability to storm surge, flooding, and sea level rise. The New York Stock Exchange closed for a week, neighborhoods and businesses were ruined, and transportation systems, such as parts of the subway, flooded. The shocking effects brought to the forefront New York’s vulnerability to coastal flooding on its unprotected coastline and its need for resilience. It was estimated that if no action is taken, New York will incur at least $500 million in damages over the next 50 years, accompanied by ripple effects across the global economy.
New York responded to the call. The current plan, part of Mayor DeBlasio’s OneNYC initiative, seeks to create a new vision of what it means to be resilient. Instead of waiting to be able to afford total flood protection throughout the five boroughs, the plan sets realistic priorities, first aimed at protecting the city’s most vulnerable people and infrastructure such as hospitals. It also seeks to quickly regain business and social continuity, quickly restoring essential services such as water, sanitation, power, transportation, and telecommunications. This multi-layered approach makes it easier for businesses and individuals to return quickly to the work of recovery.
Some key projects in New York City are expected to advance this vision, including the East Side Coastal Resiliency project, an outcome of the U.S. Department of Housing and Urban Development Rebuild by Design competition. This is the first part of an ambitious program to design and build a flood control system around Manhattan. The plan calls for a range of multifunctional resiliency solutions integrated with neighborhood and community amenities to improve community access and expand enjoyment of parks and recreational spaces.
In other parts of the world, governments have taken measures to invest in cities that are prone to flooding. For instance, China has identified sponge cities, or ones that can hold, clean, and drain water in a natural way. Unfortunately, many global cities have altered the natural systems of ponds, wetlands, and rivers by replacing them with dams, levees, and tunnels. This leads to flooded cities during major storm events. Flooding can be abated by increasing funding for returning land to natural settings, even within a concrete jungle.
Aging and inadequate infrastructure — Aging and inadequate water and wastewater infrastructure contributes to both scarcity and flooding, as well as inefficiency. The economic crisis and historically insufficient funding for water infrastructure has forced many utilities to delay improvements, which has led to a deteriorated and unreliable system. The problems associated with these issues can significantly reduce a city’s competitiveness.
But improvements are being made. Chicago, which ranks #20 in global sustainability, is addressing its efficiency vulnerability through one of the most ambitious infrastructure replacement programs on water and sewer lines, replacing 100 miles per year. To further increase efficiency and reduce consumption, the Chicago Department of Water Management has a volunteer metering program, heavily incentivizing consumers with rate guarantees to increase awareness and reduce leakage.
Climate change — Changing weather patterns threaten to leave some areas in persistent drought while others experience extreme cloud bursts, mega storms, and rising sea levels that lead to flooding. In recent years, superstorms such as Hurricane Katrina in New Orleans and Typhoon Haiyan in the Philippines produced unprecedented storm surges that devastated flood protection systems and the communities they were designed to protect. On the other end of the spectrum, California cities such as Los Angeles recently faced unparalleled water shortages.
Fortunately, resilience is now on the radar of city leadership. Boston, which ranks #16 out of 50 global cities for sustainability, is planning to build its resilience as part of its fight to combat the effects of climate change. The new Climate Ready Boston initiative is remarkable in its holistic approach aimed at reducing vulnerability to a broad range of climate change impacts, from sea level rise and flooding to extreme temperatures and intense storms.
The ambitious joint initiative of the City of Boston and the Boston Green Ribbon Commission will provide a planning framework and technical foundation for the city’s long-term climate preparedness. Boston’s goal is to produce a more detailed assessment of the city’s physical, infrastructure, environmental, and social vulnerabilities to projected climate change.
Understanding the probability of storm disruptions, heat effects, and sea level rise in Boston will help the city focus its resources where they are needed most. Addressing the important social aspects of climate risk, engaging the public, and creating a vision for the future will put Boston in the forefront of resilience planning.
Security and business continuity — The critical nature of infrastructure associated with drinking water and wastewater services makes it an obvious target of cyber hackers or other malicious adversaries. With increased automation, the focus on infrastructure security and preparedness at the utility level is on the rise. While it may be unrealistic to expect that these systems won’t be targeted, planners are bringing resilience strategies into water security systems to protect critical assets and make sure that a system can be quickly restored to service after disruptive events.
Ultimately, cities that plan ahead with their water resources will reap the advantages of an urban environment that is more attractive to its citizens, more reliable during storms and climate changes, and will provide more economic development opportunities.
Christopher Hill, P.E., BCEE, ENV SP, is vice president and Water Supply & Treatment lead with Arcadis North America (https://www.arcadis.com/en/united-states).