However, a recent study completed by researchers at Northeastern University in Boston found high concentrations of E. coli bacteria in the Charles River after a long period of no rain.
Ferdi Hellweger, Ph.D., Assistant Professor of Civil and Environmental Engineering and Acting Director of the Center for Urban Environmental Studies, both at Northeastern, used high-resolution monitoring and modeling to understand the fate and transport of E. coli bacteria in the lower section of the Charles River to determine what factors may lead to the increased concentration.
The results, which were published in the April issue of the Journal of the American Water Resources Association, go above and beyond the current data available about the water quality in the Charles and have the potential to impact the location of future beaches and their management.
Because current monitoring programs do not resolve the small-scale patterns of E. coli, Hellweger and his team carried out a high-resolution monitoring program. Using spatial and temporal surveys at different intervals and locations, Hellweger and his team gathered 757 samples along transects across and along the river, and over time at a fixed location. The results indicated an increased concentration of E. coli after a period of little rainfall.
To make sense of these results, they developed a mathematical model of the river. The model accounts for various drivers, including upstream and downstream flow, wind, combined sewer overflow (CSO) and non-CSO flow from two major tributaries, the Muddy River and the Stony Brook. Based on hydrodynamics and die-off kinetics, the model reproduced the general patterns of E. coli in the water over space and time.
“Our analysis suggests that the Stony Brook and Muddy River are the predominant sources of E. coli in the lower Charles River,” said Hellweger, whose interest in urban hydrology drove this research project. “However, it is important to determine where the bacteria go and their concentration at different times and locations.”
One surprising finding was the effect of the New Charles River Dam, which when open, allows the Charles River to flow downstream and empty into the Boston Harbor. When it is closed, however, the Charles River acts more like a lake or a reservoir, creating a static environment. Thus, in addition to rainfall, the Dam operation cycle does affect the level of bacteria in the Charles River.
“Our study results show that water quality in the Charles River is impacted by several factors, including the New Charles River Dam,” added Hellweger. “While the primary focus of the Dam is to control flooding and navigation, I think that taking water quality issues into account could help reduce public health risk to present boaters and future beachgoers in the Charles,” added Hellweger.
Their model can be used to predict water quality in the lower Charles River, which can be used to evaluate various management scenarios and assess public health risk to swimmers at different times and locations.
In a 2002 study, 25% of surveyed beaches had at least one advisory or area closed, mostly due to unsafe levels of certain forms of bacteria. Exposure to unsafe levels of bacterial can sometimes result in recreational water illnesses (RWI), causing diarrhea, respiratory, skin, ear and eye infections.
Water pollution continues to be a public health threat, and because the Summer is quickly approaching, there will be a heightened interest in protecting people who spend time in the water. “My goal is to help make the Charles River a place where people can swim safely,” said Hellweger.
Founded in 1898, Northeastern University is a private research university located in the heart of Boston. Northeastern is a leader in interdisciplinary research, urban engagement, and the integration of classroom learning with real-world experience. The university’s distinctive cooperative education program, where students alternate semesters of full-time study with semesters of paid work in fields relevant to their professional interests and major, is one of the largest and most innovative in the world. The University offers a comprehensive range of undergraduate and graduate programs leading to degrees through the doctorate in six undergraduate colleges, eight graduate schools, and two part-time divisions.
Fred McGrail | newswise
Loss of habitat causes double damage to species richness
02.04.2019 | Deutsches Zentrum für integrative Biodiversitätsforschung (iDiv) Halle-Jena-Leipzig
Deep decarbonization of industry is possible with innovations
25.03.2019 | Fraunhofer-Institut für System- und Innovationsforschung (ISI)
A stellar flare 10 times more powerful than anything seen on our sun has burst from an ultracool star almost the same size as Jupiter
A localization phenomenon boosts the accuracy of solving quantum many-body problems with quantum computers which are otherwise challenging for conventional computers. This brings such digital quantum simulation within reach on quantum devices available today.
Quantum computers promise to solve certain computational problems exponentially faster than any classical machine. “A particularly promising application is the...
The technology could revolutionize how information travels through data centers and artificial intelligence networks
Engineers at the University of California, Berkeley have built a new photonic switch that can control the direction of light passing through optical fibers...
Physicists observe how electron-hole pairs drift apart at ultrafast speed, but still remain strongly bound.
Modern electronics relies on ultrafast charge motion on ever shorter length scales. Physicists from Regensburg and Gothenburg have now succeeded in resolving a...
Engineers create novel optical devices, including a moth eye-inspired omnidirectional microwave antenna
A team of engineers at Tufts University has developed a series of 3D printed metamaterials with unique microwave or optical properties that go beyond what is...
17.04.2019 | Event News
15.04.2019 | Event News
09.04.2019 | Event News
18.04.2019 | Life Sciences
18.04.2019 | Physics and Astronomy
18.04.2019 | Life Sciences