Natural Security: Blueprint for a Model Resilient Community
While the case study communities profiled here have all adopted sustainable water management approaches that will help them weather climate change, none have implemented the strategies to the maximum extent possible or integrated multiple solutions to address community water needs comprehensively. This blueprint envisions how a hypothetical community could integrate all the strategies discussed in the case studies to become a model of resilience to the impacts of a changing climate. We ground our recommendations in the realities that communities across the country face by adopting the water management history of a real Midwestern city – we’ll call it Greenville. Starting from this city’s ongoing problems and the steps it has taken to remedy them thus far, we envision how Greenville could create a more sustainable future by holistically implementing four major initiatives.
Meeting Multiple Water Challenges
Greenville is a hypothetical community that sits on the banks of the Green River in the Midwestern US. Beginning in the 1800s, much of the area was stripped of native vegetation to make way for agriculture and a growing population. Today, Greenville is heavily urbanized and struggles with flooding, stormwater runoff, sewage overflows, a vulnerable water supply, and insufficient green space. Adding to these substantial challenges is the threat of a changing climate. Precipitation will become more variable and unpredictable, making severe storms and extended droughts more common. These storms will cause more floods, sewer overflows, and stormwater runoff. Extended dry spells combined with reduced summer precipitation and higher temperatures will decrease groundwater recharge, lower water levels in rivers, cause small streams and wetlands to dry up and threaten water supply. With less water to dilute contaminants, pollution concentrations could rise in many water bodies.
A. Water Quality and Public Health
Older parts of Greenville are served by a combined sewer system that sends billions of gallons of untreated sewage into nearby waterways every year, posing a major threat to public health, fish, and wildlife. In addition, stormwater runoff from roofs, parking lots, and streets carries nutrients, toxics, and other pollutants into the sewer system and local waterways. The challenge will only grow in a changing climate as more extreme storms overwhelm the city’s infrastructure with increasing frequency.
Greenville is currently working to address these problems by spending more than $3 billion to expand and rehabilitate its sewer system and stormwater infrastructure. While this will help improve water quality, green infrastructure solutions could provide the city with a more flexible and cost-effective approach that can be more easily adapted to changing conditions. Greenville should invest in green roofs, wetlands, rain gardens, and other techniques that will reduce stormwater and sewage pollution and help the city prepare for other challenges a changing climate will bring.
B. Storm and Flood Damage
Greenville has a long history of damaging floods. In the early 20th century, floods destroyed thousands of homes and took hundreds of lives. Between 1993 and 2005, floods caused over $100 million in property damages and took several lives. In response, the city has built a complex system of flood control dams and levees along its streams and rivers and is continuing to expand it today. This ongoing reliance on structural flood control projects provides a false sense of security that will be extremely dangerous as floods grow more severe. As we have seen time and again, in New Orleans in 2005 and along the Mississippi River in 1993, structural flood protection structures can – and do - fail. When they fail, levees and dams can unleash devastating floods that destroy property and take lives.
A safer and more cost-effective strategy would relocate vulnerable structures and restore natural flood controls. Greenville should offer buy outs to the dozens of homes and businesses that have been repeatedly damaged by floods in recent years and strictly enforce floodplain ordinances prohibiting new development in vulnerable areas. In addition, the city should restore and protect natural areas such as wetlands, stream buffers and trees throughout the city because these vegetated areas naturally retain and store rainfall, reducing peak floods. Finally, Greenville should work with upstream communities to stop and reverse the loss of wetlands and forests to agricultural activities throughout the watershed.
C. Adequate Water Supply
While Greenville does not face severe water shortages like many western communities, limited treatment capacity can cause water shortages during summer months. A moderate drought in the summer of 2007 caused water use to rise more than 50 percent and exceed the pumping and processing facilities’ capacity. In addition, the city’s water withdrawals have significant impacts on the Green River in summer, when lower rainfall and increased outdoor watering remove most of the water from the channel, degrading water quality and harming wildlife. As temperatures rise, more frequent and severe droughts will continue to tax the city’s water system and ecosystems.
Rather than undertaking a costly expansion of its water supply facilities, however, the city should address its shortages through increased efficiency and conservation. By pricing water to encourage conservation, providing incentives for the installation of water fixtures and appliances, and educating the public, the city can limit water shortages and improve the health of the rivers that supply residents with water.
D. Strong Economy and Quality of Life
Greenville bears numerous scars from poorly planned development and past economic fluctuations. Nearly all of the county’s native vegetation was destroyed during decades of intensive agriculture and rapid urbanization. Recreation on the city’s waterways is unsafe due to poor water quality. In addition, parts of downtown continue to suffer from neglect due to the economic decline of the 1960s and 1970s. These factors degrade the quality of life in Greenville and limit economic growth. A changing climate will only make the problem worse. Growing water pollution will further degrade water quality, and the lack of vegetation will magnify the consequences of rising temperatures and worsening air pollution.
Greenville is already working to ensure that it will be a vibrant, livable city even as the climate shifts. The city has created dozens of miles of recreational trails along the city’s rivers and has invested billions of dollars to revitalize its downtown. But the greenways and parks will never reach their full potential without improved water quality. The city must address its water pollution problems and continue to expand and connect parks and trails. By doing this, the city will ensure that its rivers and streams can offer recreational opportunities and strengthen an economy that will be challenged by an unpredictable climate. Additional green space will also moderate rising temperatures, reduce runoff, and make the city greener and more appealing.
Conclusion
The solutions discussed in this chapter can create a safe, healthy community capable of withstanding floods, droughts, and rising temperatures. Under this scenario, Greenville would transition from a city beset by numerous problems and vulnerable to the impacts of climate change to a vibrant, green community with healthy waterways, extensive green space, a secure water supply, improved neighborhoods, and numerous recreational opportunities. Taken together these sustainable water management strategies would make Greenville resilient to the impacts of a changing climate.
