Washington, DC, United States
Washington, DC, United States

The District of Columbia Water and Sewer Authority provides drinking water, sewage collection and sewage treatment in Washington, D.C., USA. DC Water also provides wholesale wastewater treatment services to several adjoining municipalities in Maryland and Virginia. In addition, DC Water provides maintenance and repair of more than 9,000 public fire hydrants on behalf of the District of Columbia. DC Water was created in 1996, when the District Government and the U.S. federal government established it as an independent authority of the District government.DC Water provides more than 600,000 residents, 16.6 million annual visitors and 700,000 people who are employed in the District of Columbia with water, sewage and wastewater treatment. DC Water also provides wholesale wastewater treatment for 1.6 million people in Montgomery and Prince George’s counties in Maryland, and Fairfax and Loudoun counties in Virginia.In 2010, under new leadership, the Authority underwent a rebranding effort. The rebranding included a new logo, new color palette, and a new name. Since its inception, the Authority had been doing business as DC Water. The legal name remains the District of Columbia Water and Sewer Authority. Wikipedia.

Time filter

Source Type

Fang J.,District of Columbia Water and Sewer Authority | Deng B.,University of Missouri
Journal of Membrane Science | Year: 2014

Nanofiltration (NF) membranes, DK and DL, were characterized by attenuated total reflection-Fourier transform infrared spectroscopy, surface charge titration, pore size determination and salt rejection. The results showed both membranes have amide I and carbonyl groups on their surfaces, and have the same basic structure of polyamide layer sitting on the top of a polysulfone layer. The DK membrane carries more negative charges in the entire pH range investigated. Arsenate rejections by the NF membranes were evaluated with a crossflow test setup. The effects of pH, ionic strength, operating pressure, arsenate initial concentration on the membrane performance were investigated. Mass transfer coefficients of the membranes were determined experimentally. The Donann Steric Pore Model and concentration polarization film theory were applied to calculate the arsenic rejection rate. The rejection mechanism was interpreted by calculating the contributions of convection, diffusion, and electrostatic migration to arsenic transport through the membranes. The calculated results showed that the contribution of diffusive transport dominated at low flux, and convection and electromigrative transport, especially the latter, play an increasingly important role at a high flux. © 2013 Elsevier B.V.

Bevacqua C.E.,University of Maryland College Park | Rice C.P.,Beltsville Agricultural Research Center | Torrents A.,University of Maryland College Park | Ramirez M.,District of Columbia Water and Sewer Authority
Science of the Total Environment | Year: 2011

Steroid hormones can act as potent endocrine disruptors when released into the environment. The main sources of these chemicals are thought to be wastewater treatment plant discharges and waste from animal feeding operations. While these compounds have frequently been found in wastewater effluents, few studies have investigated biosolids or manure, which are routinely land applied, as potential sources. This study assessed the potential environmental contribution of steroid hormones from biosolids and chicken litter. Hormone concentrations in samples of limed biosolids collected at a waste treatment plant over a four year period ranged from < 2.5 to 21.7. ng/g dry weight for estrone (E1) and < 2.5 to 470. ng/g dry weight for progesterone. Chicken litter from 12 mid-Atlantic farms had averages of 41.4. ng/g dry weight E1, 63.4. ng/g dry weight progesterone, and 19.2. ng/g dry weight E1-sulfate (E1-S). Other analytes studied were 17β-estradiol (E2), estriol (E3), 17β-ethinylestradiol (EE2), testosterone, E2-3-sulfate (E2-3-S), and E2-17-sulfate (E2-17-3). © 2011 Elsevier B.V.

Andrade N.A.,University of Maryland University College | Mcconnell L.L.,U.S. Department of Agriculture | Torrents A.,University of Maryland University College | Ramirez M.,District of Columbia Water and Sewer Authority
Journal of Agricultural and Food Chemistry | Year: 2010

This study examines polybrominated diphenyl ethers (PBDE) levels, trends in biosolids from a wastewater treatment plant, and evaluates potential factors governing PBDE concentrations and the fate in agricultural soils fertilized by biosolids. The mean concentration of the most abundant PBDE congeners in biosolids (∑BDE-47, BDE-99, and BDE-209) generated by one wastewater treatment plant was 1250 ± 134 μg/kg d.w. with no significant change in concentration over 32 months (n = 15). In surface soil samples from the Mid-Atlantic region, average PBDE concentrations in soil from fields receiving no biosolids (5.01 ± 3.01 μg/kg d.w.) were 3 times lower than fields receiving one application (15.2 ±10.2 μg/kg d.w.) and 10 times lower than fields that had received multiple applications (53.0 ± 41.7 μg/kg d.w.). The cumulative biosolids application rate and soil organic carbon were correlated with concentrations and persistence of PBDEs in soil. A model to predict PBDE concentrations in soil after single or multiple biosolids applications provides estimates which fall within a factor of 2 of observed values. © 2010 American Chemical Society.

Lozano N.,University of Maryland University College | Rice C.P.,U.S. Department of Agriculture | Ramirez M.,District of Columbia Water and Sewer Authority | Torrents A.,University of Maryland University College
Environmental Pollution | Year: 2012

This study investigates the persistence of Triclosan (TCS), and its degradation product, Methyltriclosan (MeTCS), after land application of biosolids to an experimental agricultural plot under both till and no till. Surface soil samples (n = 40) were collected several times over a three years period and sieved to remove biosolids. Concentration of TCS in the soil gradually increased with maximum levels of 63.7 ± 14.1 ng g -1 dry wt., far below the predicted maximum concentration of 307.5 ng g -1 dry wt. TCS disappearance corresponded with MeTCS appearance, suggesting in situ formation. Our results suggest that soil incorporation and degradation processes are taking place simultaneously and that TCS background levels are achieved within two years. TCS half-life (t 0.5) was determined as 104 d and MeTCS t 0.5, which was more persistent than TCS, was estimated at 443 d. © 2011 Elsevier Ltd. All rights reserved.

Lozano N.,University of Cantabria | Lozano N.,U.S. Department of Agriculture | Lozano N.,University of Maryland College Park | Rice C.P.,U.S. Department of Agriculture | And 2 more authors.
Water Research | Year: 2013

Triclocarban (TCC) and Triclosan (TCS) are two antibacterial chemicals present in household and personal care products. Methyltriclosan is a biodegradation product of TCS formed under aerobic conditions. TCC and TCS are discharged to Waste Water Treatment Plants (WWTP) where they are removed from the liquid phase mainly by concentrating in the solids. This study presents a thorough investigation of TCC, TCS and MeTCS concentrations in the liquid phase (dissolved+particulate) as well as solid phases within a single, large WWTP in the U.S. Total TCC and TCS concentrations decreased by >97% with about 79% of TCC and 64% of TCS transferred to the solids. The highest TCC and TCS removal rates from the liquid phase were reached in the primary treatment mainly though sorption and settling of solids. The TCC mass balances showed that TCC levels remain unchanged through the secondary treatment (activated sludge process) and about an 18% decrease was observed through the nitrification-denitrification process. On the other hand, TCS levels decreased in both processes (secondary and nitrification-denitrification) by 10.4 and 22.6%, respectively. The decrease in TCS levels associated with observed increased levels of MeTCS in secondary and nitrification-denitrification processes providing evidence of TCS biotransformation. Dissolved-phase concentrations of TCC and TCS remained constant during filtration and disinfection. TCC and TCS highest sludge concentrations were analyzed in the primary sludge (13.1±0.9μgg-1drywt. for TCC and 20.3±0.9μgg-1drywt. for TCS) but for MeTCS the highest concentrations were analyzed in the secondary sludge (0.25±0.04μgg-1drywt.). Respective TCC, TCS and MeTCS concentrations of 4.15±0.77; 5.37±0.97 and 0.058±0.003kgd-1 are leaving the WWTP with the sludge and 0.13±0.01; 0.24±0.07 and 0.021±0.002kgd-1 with the effluent that is discharged. © 2013 Elsevier Ltd.

District of Columbia Water and Sewer Authority | Date: 2015-09-09

Fertilizers; soil amendments; soil for use in turf and tree establishment, soil remediation, and green infrastructure, namely, planting soil. Top soils.

District of Columbia Water and Sewer Authority | Date: 2015-09-09

Fertilizers; soil amendments; soil for use in turf and tree establishment, soil remediation, and green infrastructure, namely, planting soil. Top soils.

District of Columbia Water and Sewer Authority | Date: 2016-06-22

fertilizers; soil amendments; soil for use in turf and tree establishment, soil remediation, and green infrastructure, namely, planting soil; top soil. shared services for utilities; providing fleet services for others; providing collections services for others; providing public utility operations services and water distribution operations services for others; public utilities in the nature of supplying water; public utility services in the nature of water distribution; utility services, namely, providing water and sewer services; water supply and distribution services; waste water treatment services for the water utility industry; peer to peer consulting for utilities; external affairs consulting, collections consulting, wastewater anaerobic digestion system consulting. waste water treatment technologies.

News Article | February 28, 2017
Site: www.prnewswire.com

WASHINGTON, Feb. 28, 2017 /PRNewswire-USNewswire/ -- The Municipal Securities Rulemaking Board (MSRB) announced today that Mark T. Kim, Chief Financial Officer of the District of Columbia Water and Sewer Authority (DC Water), will join the MSRB as Deputy Executive Director and Chief...

News Article | November 27, 2016
Site: www.gizmag.com

Global efforts to extract energy from sewage in forms such as heat, biogas and even electricity may get a boost thanks to the work of a team of biochemists and microbiologists from Ghent University in Belgium, who are collaborating on a pilot project with DC Water in Washington DC. Sewage from bathrooms and kitchens is a potential energy source because it contains various organic substances suspended in wastewater. If we want sewage treatment to be truly self-sustaining, the trick will be to find an efficient way to separate the organic matter from the wastewater – that way the wastewater can be recycled, and the organic matter can be used to generate bioenergy. Currently, the overall principle of most sewage treatment plants revolves around optimizing the way microorganisms such as bacteria, fungi and protozoans feed on the organic contaminants in wastewater. As the microorganisms eat the organic matter, they form particles that clump together and settle at the bottom of a tank, allowing a relatively clear liquid to be separated from the solids and further purified. This often includes a step called "contact stabilization," which involves using two aeration tanks to ensure the microorganisms are as active as possible before introducing them to the next batch of effluent needing treatment. At the moment, the overall sewage treatment process recovers around 20 to 30 percent of the organic matter within the sewage mix. Dr Francis Meerburg, a researcher on the Belgian project, said their aim was to improve the way bacteria captures organic material. "We periodically starve the bacteria, in a kind of 'fasting regimen'," explains Professor Nico Boon. "Afterwards, wastewater is briefly brought into contact with the starved bacteria which are gluttonous and gobble up the organic matter without ingesting all of it. This enables us to harvest the undigested materials for the production of energy and high-quality products. We [then] starve the rest of the bacteria, so they can purify fresh sewage again." This new method can recover more than 55 percent of the organic matter from the sewage, which is a big improvement over current rates of 20 to 30 percent. According to the team's calculations, this amount should provide enough energy to completely treat sewage without the need for external electricity sources. "We're not going to solve climate change with our process, but every bit helps," Vlaeminck says. "For comparison: in our region of six million people (in Flanders), the energy usage of our sewage treatment municipality, Aquafin, corresponds to the residential electricity use of more than 690,000 people (more than 10 percent of the population). This gives an idea on the energy saving potential and impact, if all sewage treatment would be energy neutral." As a clear sign that there's a strong appetite for more efficient, affordable and sustainable processes in wastewater treatment, the team's work has gone directly from the lab to a large-scale application in the USA's capital city. The researchers are currently collaborating with DC Water (the District of Columbia Water and Sewer Authority) to implement the new process on a part of the plant's full-scale water treatment installation. The next step is to evaluate how well the process can help achieve more efficient wastewater treatment on a large scale.

Loading District of Columbia Water and Sewer Authority collaborators
Loading District of Columbia Water and Sewer Authority collaborators