Written by: Sara Dennis
Not only do we need water to drink (and to make our mid-morning coffee pick-me-up), but we need and use it for a number of other things throughout the day. Washing dishes, taking a shower and watering plants are just a few examples. Having clean water to drink and get rid of wastewater safely is critical to public health. We rely on our drinking water and wastewater infrastructure to fulfill these needs, though they are rarely thought about by the average citizen.
The American Society of Civil Engineers (ASCE)’s 2017 Infrastructure Report Card (IRC) recently assessed Drinking Water Infrastructure and Wastewater Infrastructure in the United States, which earned a D and a D+, respectively. They also estimated that there will need to be a $105 billion total investment between 2016 and 2025 to meet the growing infrastructure needs.
Drinking Water
Currently there are over one million pipes throughout the US that supply our drinking water. Most of these pipes installed in the early to mid-20th century and have a lifespan of just 75-100 years, meaning that many are coming to the end of their intended use cycle, or will be in the next two to three decades. These pipes are currently replaced at a rate of 0.5% per year, meaning that at this speed, it would take 200 years to replace the current system. It’s estimated that these “leaky, aging pipes are wasting 14 to 18% of each day’s treated water” (ASCE IRC), which would support 15 million households. Furthermore, it’s estimated that there are 240,000 water main breaks per year, wasting an additional 2 trillion gallons of treated drinking water.
A reservoir in Central Park, New York City.
42 billion gallons of treated drinking water are used daily in the United States, for household uses as well as commercial and industrial needs. In most of the US, “all publicly-supplied water is treated to meet federal drinking water standards, regardless of whether it will be used for drinking” (ASCE IRC), meaning that we use drinking water in our showers, toilets, factories, etc. Approximately 80% of this water comes from surface waters – rivers, lakes, oceans and reservoirs, while the rest comes from groundwater aquifers. This makes our drinking water infrastructure vulnerable to polluted bodies of water, depleted aquifers and insufficient storage space.
According to the ASCE report, asset management “provides utility managers and decision‐ makers with critical information on capital infrastructure assets and timing of investments”. Asset management includes cataloging critical assets, evaluating condition and performance, creating plans to maintain, repair and replace assets, in addition to securing funding for improvements, and continued operations and maintenance (O&M) costs. Furthermore, cities can also invest in more green stormwater infrastructure and other programs to protect and improve our surface waters.
Wastewater
Wastewater treatment and removal is paramount to public and environmental health. When wastewater is treated, water quality is improved by reducing toxins that harm humans and pollute rivers, lakes and oceans. In the US, 76% of the population relies on the nation’s 14,748 wastewater treatment plants (WTPs). Stress on these WTPs is expected to increase by more than 23% by 2032, due to more people connecting to centralized WTPs, instead of private septic systems. With this increase, an estimated $271 billion is necessary for wastewater infrastructure.
A wastewater treatment plant (Photo by Martina Nolte licensed under CC BY-SA 3.0 de)
Wastewater enters the treatment system from residential, commercial and industrial sources through public sewer lines. The ASCE report states that “there are over 800,000 miles of public sewers and 500,000 miles of private lateral sewers connecting private property to public sewer lines. Each of these conveyance systems is susceptible to structural failure, blockages, and overflows”. The EPA estimates there are at least 23,000 – 75,000 sanitary sewer overflows annually. Additionally, in many areas of the country, stormwater also enters the system through storm drains, which causes issues when combined sewer overflows happen. While stormwater also requires collection and treatment before re-entering rivers, lakes and oceans because of trash, debris and pollutants picked up by the water, the treatment does not have to be as energy-intensive as the treatment wastewater undergoes in WTPs.
Threats to wastewater infrastructure include funding and climate change. Funding wastewater treatment projects and their O&M can be difficult, as they are usually unseen by the public eye and rarely considered. Moreover, WTPs are usually located at the bottom of watersheds, or near coastal and riverine areas, making them vulnerable to extreme flooding events and sea level rise. Several WTPs in New York and New Jersey were flooded during Superstorm Sandy, “causing hundreds of millions of gallons of untreated sewage to spill into neighboring waterways” (ASCE IRC). Now many WTPs and utility providers are now assessing their own vulnerability and developing resiliency plans.
In Conclusion
Like our current transportation infrastructure, we need to start investing and improving our water infrastructure. Locally, supporting green infrastructure can help relieve stress on WTPs in areas with combined sewer systems, as well as help keep our natural bodies of water cleaner. Furthermore, water infrastructure benefits from federal funding programs such as the State Revolving Loan Fund program under the Safe Drinking Water Act and the Clean Water Act, as well as the Water Infrastructure Finance and Innovation Act. When these programs are enacted they loan funds various entities to improve their water infrastructure systems.