Free Newsletters - Space News - Defense Alert - Environment Report - Energy Monitor
. Earth Science News .




WATER WORLD
Aging sewers impacting urban watersheds
by Staff Writers
Pittsburgh PA (SPX) Mar 13, 2013


Over a two-year period, the researchers collected water samples biweekly from the small stream located in Pittsburgh's East End during both rainy and dry time periods with intensive sampling during one summer storm.

Aging sewer systems are spilling a considerable amount of nitrogen into urban watersheds, diminishing both the quality of water and ecosystems' habitats. However, many studies documenting the impacts of nitrogen on urban environs have not properly estimated the contribution of leaky sewer systems-until now.

Using water samples from the Pittsburgh-based Nine Mile Run watershed, a Pitt research team reveals in the current issue of Environmental Science and Technology that an estimated 10 to 20 tons of reactive nitrogen from sewage flows into Pittsburgh's Monongahela River every year from the six-square-mile watershed.

That means that up to 12 percent of all sewage produced by residents living in the Nine Mile Run watershed area leaks from the sewers and is transferred to the stream, negatively affecting stream water quality.

"This is a very complicated problem," said Marion Divers, principal author of the paper and a Pitt PhD candidate who conducted the study under the supervision of Pitt assistant professors of geology and planetary science Emily Elliott and Daniel Bain, who were coauthors of the paper.

"You build a sewer system once, put it underground, and unless there's a catastrophic failure, you may not have a reason to dig it up and make sure it's not leaking. Now sewers across the United States and in Pittsburgh are aging, and as these systems grow older, more sewage is leaking into groundwater and streams."

While living organisms need nitrogen to build essential proteins, leaky sewer systems, the burning of fossil fuels, and overuse of chemical fertilizers have contributed to an overabundance of nitrogen in U.S. rivers and streams. Too much nitrogen can deplete the water of oxygen, with results as threatening as those seen in the Gulf of Mexico Dead Zone, where marine life doesn't have the oxygen necessary to live.

An estimated 10 to 20 tons of reactive nitrogen from sewage flows into Pittsburgh's Monongahela River every year from the Nine Mile Run watershed.

"Leaky sewers are simply not something most people are interested in until they begin to smell it in the stream or see things like a particular fish disappear from the stream," said Bain. "Based on the results from our Nine Mile Run study, this paper forces the wider urban ecology community to more carefully consider this sewage problem."

In order to accurately measure nitrogen's impact on Nine Mile Run, the Pitt team had to first determine how much was coming from leaky sewer systems.

Over a two-year period, the researchers collected water samples biweekly from the small stream located in Pittsburgh's East End during both rainy and dry time periods with intensive sampling during one summer storm.

Nitrogen concentrations were measured in the samples, and the researchers used this data to estimate sewage contributions to nitrogen in the stream's water. Notably, the results highlighted that sewers in this study basin are leaking consistently, even during dry weather conditions.

While the apparent volumes of sewage are concerning, the study also reaffirms the substantial ability of urban systems to hold onto this nitrogen, despite the heavily impacted stream channel and the predominance of paved areas.

"This suggests a pervasive influence of leaking sewers-even during periods without rainfall. This is in addition to the raw sewage contributions during wet weather from combined sewer overflows that are currently the subject of mitigation efforts in Pittsburgh," said Elliott. "Our report highlights the importance of assessing nitrogen leakage from sewers into our waterways, particularly as sewer systems age across the United States."

The paper, "Constraining Nitrogen Inputs to Urban Streams from Leaking Sewers Using Inverse Modeling: Implications for Dissolved Inorganic Nitrogen (DIN) Retention in Urban Environments," appeared online Feb. 17 in Environmental Science and Technology. This research was supported by the University of Pittsburgh Kenneth P. Dietrich School of Arts and Sciences, the Pennsylvania Water Resources Research Institute, the Geological Society of America, and the U.S. Steel Foundation.

.


Related Links
University of Pittsburgh
Water News - Science, Technology and Politics






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News





WATER WORLD
It's only natural: Lawrence Livermore helps find link to arsenic-contaminated groundwater
Livermore CA (SPX) Mar 12, 2013
Human activities are not the primary cause of arsenic found in groundwater in Bangladesh. Instead, a team of researchers from Lawrence Livermore National Laboratory, Barnard College, Columbia University, University of Dhaka, Desert Research Institute and University of Tennessee found that the arsenic in groundwater in the region is part of a natural process that predates any recent human activit ... read more


WATER WORLD
Earthquake Damage Can Impact Building Fire Safety Performance

India offers $532 million to states hit by drought, floods

Satellite underpins Libyan redevelopment

Fukushima status little improved

WATER WORLD
Aspirin may lower melanoma risk

NIST quantum refrigerator offers extreme cooling and convenience

Researchers Solve Riddle of What Has Been Holding Two Unlikely Materials Together

Star-shaped waves spotted in shaken fluid

WATER WORLD
Aging sewers impacting urban watersheds

Asia-Pacific facing water crisis: ADB

It's only natural: Lawrence Livermore helps find link to arsenic-contaminated groundwater

Four shark species win international trade protection

WATER WORLD
Rivers flowing under Greenland ice traced

The making of Antarctica's hidden fjords

Global warming will open unexpected new shipping routes in Arctic, UCLA researchers find

Glaciers will melt faster than ever and loss could be irreversible warn scientists

WATER WORLD
US farm land prices surge despite drought

Argentina's potash dream at risk from Vale

Thousands of dead pigs found in Shanghai river

Delayed EU phosphorus plans coming soon

WATER WORLD
Japan pays for tsunami cleanup on Canadian coast

Japan marks second tsunami anniversary

California quake revives Big One jitters

Breaking the rules for how tsunamis work

WATER WORLD
Sudan, South Sudan agree new timeline to restart oil

China congratulates Kenyatta over election win

Poll leaves Kenya still bitterly divided

South Sudan, Sudan say pulling troops from tense border

WATER WORLD
New study validates longevity pathway

Siberian fossil revealed to be one of the oldest known domestic dogs

Kirk, Spock together: Putting emotion, logic into computational words

After the human genome project: The human microbiome project




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement