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 storm events 

Member Association Events  

Western Canada Water
Watershed Hydrology & Risk Management 
Jan. 14
1–4:30 p.m.
Medicine Hat, Alberta


New England Water Environment Association
Annual Conference 
Jan. 27–30


New York Water Environment Association
Annual Meeting
Feb. 4–6
New York City


South Carolina Water Environment Association
South Carolina Environmental Conference 
March 10–12
Myrtle Beach, S.C.


Virginia WEA
Stormwater Seminar 
March 19
Richmond, Va.


Other Events 

Water Environment Research Foundation
Annual Research Forum 
Jan. 29–30
With a wet weather track 


  Dec. 6, 2012                                                Vol. 2, No. 12  

 storm feature 



Sediment Fluxes During Large Storms 

In 2011, Tropical Storm Lee dropped 102 to 178 mm (4 to 7 in.) of rain on the Susquehanna River Basin in 4 days, creating a plume of 17 million megagrams (19 million tons) of sediment that extended 161 km (100 mi) into Chesapeake Bay.

Based on initial forecasts, Superstorm Sandy, which hit the U.S. East Coast at the end of October, looked like it might produce similar results. Due to climate change, some experts anticipate that high-flow events like Sandy and Lee will become more frequent and severe, and they are a significant source of stormwater pollution.

During the past decade, Tropical Storm Lee represented only 1.8% of the Susquehanna’s flow to the bay but contributed 22% of the phosphorus and 39% of the sediment, according to a 2012 report released by the U.S. Geological Survey (USGS). In 2011 alone, Lee contributed 78% of the sediment flowing into the bay from the Susquehanna River.


Trouble behind the dam 

In the Chesapeake Bay, high flow events further affect water quality due to aging dams on the Susquehanna River — the largest tributary feeding into the bay. The Susquehanna is also the largest source of sediment and phosphorus to the bay, and more than 91 million megagrams (100 million tons) of sediment lie behind the 84-year-old Conowingo Dam near the river’s mouth.

Over the years, sediment has filled the reservoir to about 85% of its capacity, and researchers estimate that it will be full by 2020.

“The Conowingo Dam was a very effective best management practice [BMP] controlling the input of sediment and phosphorus into the Chesapeake Bay, but this BMP is nearing the end of its useful life,” said Robert Hirsch, a USGS research hydrologist. “Those responsible for the river and for the bay are going to have to come to grips with this fact.”

As reservoir capacity decreases, so does the reservoir’s ability to trap sediment and nutrients, especially during flood events. Because of this, contributions from the Susquehanna River are already undermining efforts to comply with the Chesapeake Bay total maximum daily load, which targets sediment, nitrogen, and phosphorus.

 “Even with control measures upstream, which we think are fairly effective, we are actually seeing an increase in phosphorus flowing into the bay from the Susquehanna River,” Hirsch said.

Once the reservoir reaches its sediment storage capacity, a 250% increase in sediment and 70% increase in phosphorus is expected, compared to mid-1990s levels, according to a 1997 USGS report.


Chesapeake Bay after Lee 
The plume of sediment caused by Tropical Storm Lee, taken by Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite (Sept. 13)


 Monitoring and maintenance 

“The lesson about this reservoir is the importance of monitoring BMPs and assessing their effectiveness, because effectiveness can change significantly over time,” Hirsch said. “A few decades ago, Conowingo Dam was trapping a significant amount of sediment and phosphorus. Now, it is becoming a source.”  

“You can’t just assume that a BMP will continue to work the same way decade after decade; you have to monitor and analyze the data to see what is happening,” Hirsch said.


Finding solutions 

Researchers working on the Lower Susquehanna River Watershed Assessment are reviewing solutions to reservoir sedimentation. The primary option under review is reservoir dredging. However, this option is expensive; the sediments must be stable on the landscape, once moved; and they contain legacy pollutants.  

Another option is allowing sediment to bypass the reservoir and moving it into the bay during late fall or winter. During this time, phosphorus is less biologically active and would be less likely to harm the bay.


Broader implications 

Serena McClain, director of river restoration at American Rivers, estimates that there are about 100,000 dams in the U.S., many of which are older, smaller dams that have filled in.  

“Dams weren’t built to manage sediment, and most don’t have sediment management plans behind them,” McClain said.

“Rivers move sediment,” McClain said. “The question is, are they moving excessive amounts of sediment due to impacts on the watershed? The dam isn’t the crux of the problem. We need to look at solutions that minimize impacts to the watershed upstream.” And, stormwater management solutions must focus on both large and small storms. Small events, such as 1.5 year storms, generate more sediment delivery over time. However, large pulses associated with high flow events may have more immediate adverse impacts on water quality.

Unfortunately, in the Susquehanna River Basin, “sedimentation seen today is not really driven by current land use practices but by agricultural practices used 100 years ago,” Hirsch said. The sediment eroded and deposited in flood plains and reservoirs from agricultural land upstream is gradually being eroded by the storms that pass through.


 Storm news 


WEF Co-Hosts Water Quality Trading Workshop  

/uploadedImages/Access_Water_Knowledge/Stormwater_and_Wet_Weather/Stormwater_Reports/stormdrain(1).jpgOn Nov. 28 and 29, the Water Environment Federation, World Resources Institute, and U.S. Environmental Protection Agency (EPA) held two workshops on water quality trading in Washington, D.C. The event was broadcast at no charge to nearly 800 attendees, and the recording and presentations will be archived online.

The first day, hosted by EPA, focused on needs and perspectives of potential buyers and sellers, as well as the stakeholders they interact with. Representatives from publicly owned treatment works, agriculture, technology, and finance sectors presented information on various aspects of water quality trading. On the second day of the event, speakers dug into technical aspects of trading, such as local water quality issues, the development of baselines, and ensuring additionality in market frameworks. Researchers, regulators, and practitioners in trading discussed these topics, as well as the emerging role of stormwater and municipal separate storm sewer systems in trading programs.


Superstorm Sandy Affects Water and Wastewater Utilities  

pondOn Oct. 29, Superstorm Sandy made landfall over southern New Jersey. According to news sources, the 1290-km-wide (800-mi-wide) storm is responsible for 125 U.S. deaths and $62 billion in damage, primarily in New York and New Jersey. Sandy also affected more than 100 water and wastewater facilities — disrupting treatment, pump stations, and distribution due to flooding, lost power, pipeline breaks, and sewer overflows.

The Passaic Valley Sewerage Commission (PVSC), which flooded and lost power, is the fifth-largest treatment plant in the U.S. and receives municipal and industrial waste from 48 municipalities near Newark, N.J. Water Environment Federation (WEF) staff and volunteers worked with the U.S. Environmental Protection Agency to help PVSC and others by identifying facilities able to provide technical assistance and mobile equipment as well as those able to potentially receive solids while affected systems are repaired.

The Water/Wastewater Agency Response Network (WARN) and other resources are available to provide assistance during emergencies. Read more about preparing for and recovering from disasters in the December WEF Highlights.


U.S. Supreme Court Hears Controversial Case on Stormwater  

storm drainOn Dec. 4, the U.S. Supreme Court heard a case — L.A. County Flood Control District vs. National Resources Defense Council (NRDC) — focusing on stormwater discharges in the Los Angeles area. During oral arguments, all parties in the case agreed that the transfer of water through concrete-lined sections of the Los Angeles and San Gabriel Rivers does not constitute a “discharge” under the National Pollutant Discharge Elimination System (NPDES) municipal separate storm sewer system (MS4) permit held by the flood control district (District).

Oral arguments during the Dec. 4 case also focused on the scope of the District’s responsibility, under the compliance monitoring regime of its MS4 permit, for pollution detected at the in-river monitoring stations, regardless of any demonstrated connection to the District’s stormwater outfalls.

Arguments also addressed the Supreme Court’s options.  It could reverse the Ninth Circuit decision outright or vacate the case, remanding it back to the Ninth Circuit to re-hear the issue of the District’s responsibility under their permit’s compliance monitoring regime.  Although the Ninth Circuit previously rejected the District’s argument regarding permit interpretation, it might reconsider once the Supreme Court officially rules on the discharge issue.  


U.S. Supreme Court May Refuse Logging Road Stormwater Case in Light of U.S. EPA Rule   

On Dec. 3, the U.S. Supreme Court heard oral arguments in an Oregon logging road pollution case that has been litigated since 2006. The court agreed to review the 9th Circuit Court’s decision to consider stormwater runoff channeled from logging roads as a point source requiring a Clean Water Act permit.  However, the U.S. Environmental Protection Agency (EPA) issued a new rule Nov. 30 clarifying that polluted runoff from logging roads should not be considered a point source under the Clean Water Act and is therefore exempt from regulatory requirements.  Chief Justice John Roberts said the justices were “surprised” by EPA's 11th-hour rule change. The justices then proceeded to discuss whether they should even consider the case in light of EPA’s rule. If the case is not heard, there is concern that ambiguity in the law will remain. Additionally, the attorney representing the logging industry stated that a ruling by the high court could provide legal clarity for future litigation. The Supreme Court should indicate soon if it plans to decide the case on its merits.


 USGS Samples Waterbodies Affected by Superstorm Sandy 

The U.S. Geological Survey (USGS) collected data during and after Superstorm Sandy to determine its impacts on water quality and streamflow. Sampling afterward has included more in-depth testing for nutrients, pesticides, and bacteria. Results can be found online.

New Jersey sampling sites include the Delaware River near Trenton and the Raritan River near Queens Bridge. In Pennsylvania, researchers are sampling the Chesapeake Bay. In Maryland, samples are being taken from the Potomac River, the Eastern Shore, and the Susquehanna River at Conowingo Dam. Crews are also sampling northern Virginia and Washington, D.C., sites. Read more.


WERF Releases Sustainable Integrated Water Management RFP  

The Water Environment Research Foundation recently released a request for proposals (RFP) supporting the Sustainable Integrated Water Management program, which seeks to move utilities toward a “One Water Paradigm.” This RFP focuses on institutional issues and governance structures affecting established drinking water, wastewater, and stormwater utilities. The RFP also calls for ways of adopting the One Water Paradigm, including case examples and barriers to its implementation. Proposals are due Jan. 14, and $100,000 in funding is available. Read more.


North Texas Land/Water Sustainability Forum Announces Winners of Low-Impact Development Competition 

On Nov. 12, the North Texas Land/Water Sustainability Forum announced the winners of its low-impact development competition. Judges included top North Texas developers, as well as civic and governmental leaders. Nine finalists competed for four first-place positions in the categories of green roadways, urban redevelopment, mixed-use redevelopment, and mixed-use development. Project requirements dictated that submissions be adapted to North Texas conditions, provide water quality benefits, and restore natural habitat while enhancing natural aesthetics. The sustainable projects also demonstrated cost savings over traditional development. View a full list of the winners. Watch presentations from the finalists here.


USGS Study Shows Effects of Urbanization on Streams 

A recent study by the U.S. Geological Survey (USGS) found that sensitive species loss can occur during the earliest stages of urban development. In addition, there is no single factor responsible for stream degradation. Previous though was that stream systems are resilient up to certain levels of impervious cover (typically 0–10%) within a watershed. However, this study shows that streams are actually much more sensitive, with sensitive species loss occurring with relatively small increases in impervious cover. The study looked at nine metropolitan areas across the U.S., and USGS also developed a modeling tool for determining the best actions for reducing certain stream stressors. The tool, known as the Biological Conditional Gradient (BCG), is based on conditional probability to improve the biotic integrity of impacted streams through the use of stream restoration or urban stormwater best management practices. 

On Nov. 30, the U.S. presented findings from this study on the effects of urbanization on streams at a briefing presented by the Northeast Midwest Institute and Water Environment Federation, along with congressional hosts U.S. Sen. Benjamin Cardin (D–Md.) and U.S. Rep. Donna Edwards (D–Md.). Read more and check out the corresponding videos.


U.S. EPA Releases 2012 Recreational Water Quality Criteria 

On Nov. 26, the U.S. Environmental Protection Agency (EPA) announced the release of new recreational water quality criteria. The new criteria are not prescriptive but are intended to serve as a tool for states to use in setting their standards. The 2012 standards are also intended to improve protection of public health by including a broader range of illness symptoms, better accounting for pollution after heavy rain, more-protective recommendations for coastal waters, rapid water testing, and early alerts for swimming advisories. With the standard, EPA also provides tools for evaluating water safety, managing recreational waters, and determining pollution sources.


 NOAA Awards $5.5 Million in Watershed Education Grants 

The U.S. National Oceanic and Atmospheric Administration (NOAA) recently awarded $5.5 million in K–12 education grants for watershed studies as part of the agency’s Office of Education Bay Watershed Education and Training (B-WET) Program. Examples of winning projects include field investigations in the Gulf of Mexico, stormwater management studies in the Great Lakes, and creating urban schoolyard habitats in the Chesapeake Bay. Projects are meant to be responsive to regional environmental priorities, and focus areas include California, Chesapeake Bay, the Great Lakes, the Gulf of Mexico, Hawaii, New England, and the Pacific Northwest. NOAA also provides formal K–12 educator training programs.

Through the B-WET program, NOAA has supported more than 680 projects with more than $50 million. The request for applications for 2013 grants is coming to a close, but this page has information on all NOAA Office of Education funding announcements. Read more.


 SWEMA Draft Maintenance Agreement for Stormwater Controls  

With many stormwater controls being implemented on private land, property owners should be aware of long-term operation and maintenance and associated costs. The Stormwater Equipment Manufacturers Association recently released a draft maintenance agreement that can be used by state and local governments to require property developers or owners to perform routine maintenance of stormwater controls. Also included in this document is guidance on additional items to include in the operation and maintenance agreement, such as a long-term maintenance plan written by a design engineer and a map of the stormwater controls. Finally, the document contains guidance on the frequency of monitoring and maintenance for various stormwater controls.


Los Angeles Enacts New Municipal Stormwater Permit   

In mid-November, the Los Angeles Regional Water Quality Control Board issued a new National Pollutant Discharge Elimination System (NPDES) municipal separate storm sewer system (MS4) permit. The stormwater permit set total maximum daily loads (TMDL) for 33 pollutants and covers Los Angeles County and 84 cities within the Los Angeles County Flood Control District — an area spanning 7770 km2 (3000 mi2). The Los Angeles County Public Works Department is viewing this as an opportunity to manage water resources in a more holistic way and to protect water quality with green infrastructure.

However, the regulation does not guarantee compliance, because there are no penalties for plans that do not meet Clean Water Act standards, according to environmental groups. In addition, these groups claim that there has been slow progress in remedying water quality in waters previously listed as impaired. Some cities were also in opposition to the regulation, saying it would be too costly to improve stormwater controls over such large areas.


 Toolkit Aims to Improve Collaboration on Source Water Protection   
The Source Water Collaborative and U.S. Natural Resources Conservation Service recently launched a toolkit to help protect drinking water sources through agricultural conservation practices. The toolkit is a guide to fostering effective collaboration with state and regional U.S. Department of Agriculture partners. It lists opportunities, key contacts, additional resources, and partners, as well as success stories. The Source Water Collaborative is developing a supplement with the National Association of Conservation Districts that is a guide to working with conservation districts. 


City of Santa Barbara, Calif., and University of California Release Source Tracking Guidance   

Using microbial markers and other methods, source tracking can help identify sources of fecal pollution in stormwater and receiving waterbodies. Knowing the source of fecal pollution is an important first step to finding effective ways of eliminating it. The City of Santa Barbara, Calif., and the University of California–Santa Barbara recently released a guidance document that outlines test tools for tracking human waste signals. This research was driven by potential health hazards to beachgoers, as some Santa Barbara storm drains were discharging human waste. Researchers used methods outlined in the guidance document to identify four sites with persistently leaking sewage that were repaired immediately. Read more.


Check It Out! 

Post ItThe Massachusetts Institute of Technology CoLab Green Economic Development Initiative (GEDI) is calling on stormwater management professionals, designers, engineers, and contractors to complete a 10-minute Green Infrastructure Survey.  This survey will inform a study of job and economic development opportunities in green infrastructure.  Cities and stormwater authorities increasingly recognize that investments in green infrastructure can aid stormwater management, enhance local ecology and beautify neighborhoods. What is more, investments in green infrastructure may create greater opportunities for local small businesses and lesser skilled workforces.  However, the extent of economic development opportunities associated with green infrastructure is not well understood, nor have cities articulated comprehensive strategies for integrating economic development priorities into their green infrastructure planning and implementation.  Individual data will remain confidential, and will be reported only on an aggregate level, not on a firm-level basis.