Featured Research

from universities, journals, and other organizations

First evaluation of the Clean Water Act's effects on coastal waters in California reveals major successes

Date:
April 26, 2012
Source:
University of Southern California
Summary:
Levels of copper, cadmium, lead and other metals in Southern California's coastal waters have plummeted over the past four decades, which researchers attribute to sewage treatment regulations that were part of the Clean Water Act of 1972 and to the phase-out of leaded gasoline in the 1970s and 1980s.

Levels of copper, cadmium, lead and other metals in Southern California's coastal waters have plummeted over the past four decades, according to new research from University of Southern California.

Samples taken off the coast reveal that the waters have seen a 100-fold decrease in lead and a 400-fold decrease in copper and cadmium. Concentrations of metals in the surface waters off Los Angeles are now comparable to levels found in surface waters along a remote stretch of Mexico's Baja Peninsula.

Sergio Sañudo-Wilhelmy, who led the research team, attributed the cleaner water to sewage treatment regulations that were part of the Clean Water Act of 1972 and to the phase-out of leaded gasoline in the 1970s and 1980s.

"For the first time, we have evaluated the impact of the Clean Water Act in the waters of a coastal environment as extensive as Southern California," said Sañudo-Wilhelmy, professor of Biological and Earth sciences at the USC Dornsife College of Letters, Arts and Sciences.

"We can see that if we remove the contaminants from wastewater, eventually the ocean responds and cleans itself. The system is resilient to some extent," he said.

The USC researchers compared water samples from roughly 30 locations between Point Dume to the north and Long Beach to the south to samples taken in the exact same locations in 1976 by two researchers at the University of California, Santa Cruz: Kenneth Bruland and Robert Franks.

"We wanted to assume that the Clean Water Act was working, but we needed good data to allow us to compare water conditions 'before and after,'" he said. "Fortunately for us, we have the data generated by Bruland and Franks. That gave us a rare opportunity to see the impact of cleaning our sewage and see the effect on the coastal ocean. The population of Southern California has increased in the last 40 years, the sewage treatment has been improved, and the levels of metals in the coastal ocean have declined."

Sañudo-Wilhelmy's team -- which includes USC doctoral researcher Emily A. Smail and Eric A. Webb, associate professor at USC Dornsife -- published its findings this month in Environmental Science and Technology.

This research was funded by the USC Sea Grant program.


Story Source:

The above story is based on materials provided by University of Southern California. Note: Materials may be edited for content and length.


Journal Reference:

  1. Emily A. Smail, Eric A. Webb, Robert P. Franks, Kenneth W. Bruland, Sergio A. Sañudo-Wilhelmy. Status of Metal Contamination in Surface Waters of the Coastal Ocean off Los Angeles, California since the Implementation of the Clean Water Act. Environmental Science & Technology, 2012; 46 (8): 4304 DOI: 10.1021/es2023913

Cite This Page:

University of Southern California. "First evaluation of the Clean Water Act's effects on coastal waters in California reveals major successes." ScienceDaily. ScienceDaily, 26 April 2012. <www.sciencedaily.com/releases/2012/04/120426134931.htm>.
University of Southern California. (2012, April 26). First evaluation of the Clean Water Act's effects on coastal waters in California reveals major successes. ScienceDaily. Retrieved April 24, 2014 from www.sciencedaily.com/releases/2012/04/120426134931.htm
University of Southern California. "First evaluation of the Clean Water Act's effects on coastal waters in California reveals major successes." ScienceDaily. www.sciencedaily.com/releases/2012/04/120426134931.htm (accessed April 24, 2014).

Share This



More Earth & Climate News

Thursday, April 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deadly Fungus Killing Bats, Spreading in US

Deadly Fungus Killing Bats, Spreading in US

AP (Apr. 24, 2014) — A disease that has killed more than six million cave-dwelling bats in the United States is on the move and wildlife biologists are worried. White Nose Syndrome, discovered in New York in 2006, has now spread to 25 states. (April 24) Video provided by AP
Powered by NewsLook.com
New Pictures of Ship That Sank in 1888

New Pictures of Ship That Sank in 1888

AP (Apr. 24, 2014) — Federal researchers have released new images of the City of Chester, a steamship that sank in San Francisco Bay in 1888. Researchers recently found the shipwreck while mapping shipping routes. (April 24) Video provided by AP
Powered by NewsLook.com
Risk of Asteroid Hitting Earth Higher Than Thought, Study Shows

Risk of Asteroid Hitting Earth Higher Than Thought, Study Shows

Reuters - US Online Video (Apr. 23, 2014) — A group of space explorers say the chance of a city-obliterating asteroid striking Earth is higher than scientists previously believed. Deborah Gembara reports. Video provided by Reuters
Powered by NewsLook.com
UN Joint Mission Starts Removing Landmines in Cyprus

UN Joint Mission Starts Removing Landmines in Cyprus

AFP (Apr. 23, 2014) — The UN mission in Cyprus (UNFICYP) led a mine clearance demonstration on Wednesday in the UN-controlled buffer zone where demining operations are being conducted near the Cypriot village of Mammari. Duration: 01:00 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins