What Is the 1972 Clean Water Act and Has it Worked?

The available of clean drinking water has consistently ranked at the top of everyday Americans’ environmental concerns for half a century. With that in mind, the government introduced the Clean Water Act in 1972, which set out parameters for industrial companies to follow, prohibited the discharge of unclean wastewater into public rivers and streams and imposed penalties on those who broke the law.

Since its inception 46 years ago, the Clean Water Act has shown remarkable results in cleaning up US waterways. According to the first comprehensive review of how water quality has been affected by the legislation over the last few decades, water quality has been boosted significantly - but the improvements have come at substantial financial cost which, in purely economic terms, heavily outweighs the benefits that the Clean Water Act has engendered.

Making sense of the data

Maintaining river conservation necessarily involves high-resolution monitoring, but this is where the authors of the study ran into problems. Unlike air or soil pollution, there is no standardised system of observation; instead, water quality data often relies on independent sources supplying their own (potentially flawed) results.

In order to compile their study, the researchers from Iowa State University teamed up with the University of California, Berkeley to analyse more than 50 million pieces of data, picked up at almost a quarter of a million monitoring locations over the course of almost 40 years from 1962 to 2001. “It was an incredibly data- and time-intensive project to get all of these water pollution measures together and then analyse them in a way that was comparable over time and space,” explained Joseph Shapiro, an author on the paper.

Positive results

In over half of the measures of water pollution analysed by the team, the samples showed improvement. Some of these included an impressive hike in dissolved oxygen concentrations in the water and a corresponding drop-off in faecal coliform bacteria, both of which contributed to a 12% increase in the number of rivers deemed fit for fishing between 1972 and 2001.

Elsewhere, significant investment in improved mill performance and wastewater treatment at industrial sites had led to a marked uptick in the quality of water tested at locations downstream of sewage processing plants. In many cases, this investment was driven by grants and subsidies issued by municipal authorities to allow plants to clean up their operations.

The price of clean water

Despite the encouraging results, the study also uncovered a huge disparity in the financial benefits of the Clean Water Act when measured against the costs it had incurred. The aforementioned grants cost a cumulative $650 billion, while the team also calculated that cleaning up just one mile of a river or stream for one year to make it safe for fishing had cost a whopping $1.5 million.

By contrast, the benefits relayed by these improvements - such as a rise in water-facing properties or reduced travel times to source a good fishing spot - amounted to less than half the overall outlay. However, the fact that the adverse effects of drinking unclean water were not factored into the calculations has prompted the authors of the study to profess they believe the projected economic benefits may be an underestimation.