Monday, February 27, 2017

Drought is Building in Virginia

Yellow is dry, tan is drought 2/21/2017

In their weekly report last week the U.S. Drought Monitor published by the National Oceanic and Atmospheric  Administration (NOAA) and Department of Agriculture reported that the precipitation that fell in the previous week continued to reduce long-term drought in California and contracted drought in the Southern Plains, but dry conditions in the Mid-Mississippi Valley, Southeast, and Mid-Atlantic expanded drought. At this time over 12% of Virginia was in drought and over half the Commonwealth was experiencing abnormally dry conditions. The dry conditions expanded beyond Virginia in the Chesapeake Bay area; and drought expanded eastward across northeast Maryland, northern Delaware, and southern New Jersey. 

Rainfall and snow melt are the water that flows to the rivers and streams of the watershed, but also percolates into the ground and recharges the groundwater. Private drinking water wells draw their water from groundwater and over 20% of Virginians depend on private wells for their drinking water. Geology, climate, weather, land use and many other factors determine the quality and quantity of the groundwater, so I keep my eye on the precipitation. Prince William is unique in having four distinct geologic provinces that come together in the County: (1) the Blue Ridge, (2) the Culpeper Basin, (3) the Piedmont, and (4) the Coastal Plain. Last fall the groundwater level in the U.S. Geological Survey (USGS) monitoring well up the road from my home in the Culpeper Basin geology recorded its lowest level in 86 years and we were not even officially in drought at that time. That’s when I began to worry about my water supply.

It is concerning that the seasonal lows are getting lower. This is a sign that the present groundwater use may not be sustainable. No studies have been done that attempt to quantify what the total available water is within the county or any of the geologic provinces where residents depend on groundwater for drinking water supply. Thus, it is impossible to know if the overuse or diminished recharge of the aquifer is critical yet. According to studies by a group of researchers at the University of California, Irvine, the University of Texas, and the Hydrological Sciences Branch of NASA at GSFC using satellites to perform real world groundwater monitoring Virginia’s aquifers are under stress. That means that we are using up the groundwater faster than it is recharging. That is exactly what would cause an 86 year low level of groundwater when we were not yet in a drought. Now with all of Prince William County in drought, there is no relief in sight though a wet spring could alleviate the drought.

My well draws water from an unconfined aquifer. A water-table, or unconfined, aquifer is an aquifer whose upper surface is the water table, and is at atmospheric pressure. The water table rises and falls with moisture content that is contained in the soil, and right now the area is in drought and the water table level is falling. Water-table aquifers are usually shallower than confined aquifers and because they are shallow, they are impacted by drought conditions much sooner than confined aquifers.

The northwestern part of Prince William County down the hill from Bull Run Mountain consists of sedimentary rocks of the Culpeper Basin. The predominant rock types are conglomerates, sandstones, siltstones, shales, and argillaceous limestones. When there is rain and snow melt, this geology tends to have wonderful water-bearing potential because it is a fractured rock system with very little overburden. The highest reported yields in the county are from wells in this geology. The downside is that this area is susceptible to contamination- the fractures that carry water can easily spread a contaminant and without adequate overburden spills could flow to depth through a fracture; and there is limited water storage within the fractured rock system. An extended drought could significantly impact my well and the other wells in this area.

Thursday, February 23, 2017

Alzheimer’s, Blood Flow and Air Pollution

Scientists at the Montreal Neurological Institute and Hospital analyzed more than 7,700 brain images from 1,171 people in various stages of Alzheimer’s progression using a variety of techniques including magnetic resonance imaging (MRI) and positron emission tomography (PET). Blood and cerebrospinal fluid were also analyzed, as well as the subjects’ level of cognition. The researchers found that, contrary to previous understanding, the first physiological sign of Alzheimer’s disease is a decrease in blood flow in the brain. An increase in amyloid protein was considered to be the first detectable sign of Alzheimer’s. While amyloid certainly plays a role, this study finds that changes in blood flow are the earliest known warning sign of Alzheimer’s. The study also found that changes in cognition begin earlier in the progression than previously believed.

The Montreal Neurological Institute and Hospital – The Neuro – is a world-leading destination for brain research and advanced patient care. The Neuro has grown to be the largest specialized neuroscience research and clinical center in Canada, and one of the largest in the world. This study is one of the most thorough ever published on the subject of Alzheimer’s disease progression. The study used multiple imaging techniques to measure amyloid concentration, glucose metabolism, cerebral blood flow, functional activity and brain atrophy in 78 regions of the brain, covering all grey matter.

Late-onset Alzheimer’s disease is an incredibly complex disease that is not caused by any one neurological mechanism but is a result of several associated mechanisms in the brain. Late-onset Alzheimer’s disease is the most common cause of human dementia and an understanding of the interactions between its various mechanisms is important to develop treatments.

Emerging evidence suggests that there is a link between air pollution and dementia. Last month researchers at the University of Toronto published a study in The Lancet that found that dementia is more common in people who live within 50 meters of a major road than those who live further away. The researchers tracked all adults between the ages of 20 and 85 living in Ontario, Canada- approximately 6.6 million people - from 2001 to 2012. They used the Canadian postcodes to determine how close people lived to a road and analyzed medical records to see if they went on to develop dementia or other diseases. They found that over the study period, more than 243000 people developed dementia and those living within 50 meters of a major rad were 12% more likely to develop dementia. The researchers believe that fine particulate pollutants which are often 10 times higher near major roads are the cause.

Though the link between air pollution as fine particulates and dementia remains controversial, a growing number of epidemiological and animal studies are beginning to support that link. The association of inhaling fine particulates and heart disease has become well established, now with mounting evidence of accelerating cognitive aging and even increased risk of Alzheimer’s disease more research is needed to develop a deeper understanding of functioning of the brain. Possibly, inhaled particulates impair blood flow to the brain.  If you want to take a look at real time particulate pollution levels you can see what the monitors nearest your home are reporting. 

Alzheimer's disease is a progressive loss of memory and cognition, for which there is no cure. In Alzheimer’s disease aggregates of beta-amyloid form plaques between brain cells that is believed to contribute to the disease process, but in one of the earliest studies, the Nuns Study, beta-amyloid plaques were present when there were no signs of cognitive decline. Funding for research for treatment for Alzheimer’s disease gave a primary role for amyloid-in Alzheimer's disease, but treatment strategies targeted at reducing amyloid-have failed to reverse cognitive symptoms. These clinical findings suggest that cognitive decline is the result of a complex pathophysiology and that targeting amyloid-alone may not be sufficient to treat Alzheimer's disease. It also suggests that there will be no cure.

Monday, February 20, 2017

WSSC Break Spills Millions of Gallons of Sewage

On February 9th 2017 a 20-inch pressurized sewer main at the at the Piscataway Wastewater Treatment Plant on Farmington Road in Accokeek ruptured; releasing millions of gallons of sewage into Piscataway Creek. The Piscataway Plant treats about 24 million gallons of wastewater per day. For about 10 hours almost half of all sewage reaching the plant was flowing to the creek as raw sewage until Washington Suburban Sanitary Commission (WSSC) workers were able to divert the flow into retention basins at the plant. Drinking water supplies were not impacted. 

Over the February 10th weekend, WSSC crews and contractors installed temporary pumps and bypass piping at the Piscataway Wastewater Treatment Plant. The bypass diverted the majority of the wastewater flow directly into the plant for treatment. The remainder of the flow was being pumped into retention basins on plant grounds will be treated at a later date.
from WSSC

WSSC crews continued their around-the-clock repairs. By the middle of last week the WSSC crews were able to reach an important milestone in the containment and repair process -they finished installing a second set of temporary pumps and bypass pipes, allowing all wastewater to bypass the break and be safely pumped into the plant for treatment. This means that wastewater is no longer being pumped into the on-site retention basins.

WSSC now has two sets of temporary pipes, each 2,000 feet in length, moving wastewater around the broken sewer main to the plant. A third set of temporary bypass pipes and pumps will be constructed and, if needed, put into service. It took several days to excavate the broken pipe for examination because it was located under a concrete-encased structure that contained approximately 120-feet of high-voltage lines. The electric lines were de-energized and the concrete encasement broken apart.

The 20-inch sewer main pipe is made of cast iron and is 52-years old. Experts analyzed the pipe late last week and determined that at least 60-feet of the 88 foot pipe needs to be replaced. A decision will be made on the remaining 28-feet of pipe after it is inspected. Given the costs in terms of environmental damage, and emergency response should push WSSC to replace the entire span of the pipe rather than see if they can get a few more years of service out of the 28 feet.
from WSSC

The replacement pipe was expected to be onsite this weekend. It will take at least a week to install all sections of the new pipe. WSSC has more than 5,500 miles of sewer mains throughout its service area. This pipe break last week and the growing number of drinking water and sewage breaks in the past couple of years serves to highlight the issue of aging infrastructure in the WSSC’s system and America. WSSC is in the middle of capital projects to replace 2,000 miles each of sewer and water mains.

Ideally, pipe replacement occurs at the end of a pipe’s “useful life”; that is, the point in time when replacement or rehabilitation becomes less expensive in going forward than the costs of numerous unscheduled breaks and associated emergency repairs; rather than waiting for a pipe to fail. Age alone, however, cannot always be used as an indicator of failure, but it is a good predictor in warm weather breaks.

In cold weather more pipes fail. There is a relationship between water temperature and pipe breaks. A sudden temperature drop provides a kind of shock to the pipes especially when the pipes are older. The recent warm weather punctuated by cold snaps may have contributed to the break happening now. Water temperature below 40 degrees Fahrenheit can also cause pipes to become more brittle, and break. That leads to increased pipe breaks in the winter, and why water utilities typically report their February number of breaks- when most breaks take place. For the last decade WSSC pipe replacement program has had more unscheduled emergency repairs in winter.

Remember WSSC’s water and wastewater systems are separate. This overflow did NOT affect WSSC’s drinking water.

Thursday, February 16, 2017

Gas Pipeline Protest in Maryland

A group of about 100 protesters peacefully dominated a Hancock Maryland Town Hall meeting hosted by Columbia Gas Transmission who is proposing a new 3.9 mile, 8-inch diameter pipeline to connect Mountaineer Gas (the West Virginia consumer gas distribution company) to gas supplies in Pennsylvania. The proposed pipeline will be run about 72 feet below the river bed. The new pipeline will bring gas from the Marcellus Shale in Pennsylvania and Ohio to a new proposed Mountaineer Gas pipeline, The Mountaineer Xpress project. 

Columbia Pipeline Group, Inc. (Columbia)  is planning to construct and operate approximately 165 miles of pipeline and three new compressor stations in addition to upgrading three existing compressor stations and one regulating station. The project called the Mountaineer XPress project (MXP) would be able to move an additional 2.7 billion cubic feet per day of natural gas from the Marcellus and Utica shale production areas to commercial and consumer markets on the Columbia Gas Transmission system, including markets in western West Virginia.

The Mountaineer XPress project will facilitate continued use of a domestically-produced, low-cost source of energy that yields significantly lower emissions than its alternatives while reducing the nation’s dependence on foreign sources of energy. However, much of the natural gas from the Marcellus and Utica shale is obtained by using hydraulic fracturing methods also called fracking. This is why protesters organized by Occupy Washington DC dominated a meeting at the Hancock Maryland Town Hall. The meeting was meant to be an informational meeting about  the pipeline, which is intended to go under the C & O Canal and Potomac River. Representative from Columbia Gas were present to answer questions. 

The Mountaineer XPress Pipeline project is a significant financial investment in the state of West Virginia. According to an economic impact study conducted by Witt Economic LLC, close to 9,000 jobs will be created during the length of this project. In addition to the jobs created, the project will also generate new tax revenue for the local communities. This meeting was part of Columbia’s outreach to landowners and communities in areas where the Mountaineer XPress project will be constructed.  The Occupy Washington, DC organized group, pledged a sustained campaign against the project and their group is prepared to protest, blockade and legally challenge the pipeline every step of the way. The group says that they want to defeat the pipeline and move on to a better world powered only by solar and wind energy. 

In July 2016, TransCanada (the pipeline company who wanted to build the KeystoneXL Pipeline) completed the acquisition of Columbia Pipeline Group, Inc. (Columbia) for $13 billion. Columbia operates approximately 15,000 miles of regulated natural gas pipelines that extend from New York to the Gulf of Mexico. Columbia delivers  natural gas to the energy markets, serving customers in more than 16 states throughout the northeast and gulf. In addition, Columbia  also owns and operates one of North America’s largest underground natural gas storage systems that includes 37 storage fields in four states with over 650 billion cubic feet in total capacity, and their Hardy Storage operation has a working storage capacity of 12 billion cubic feet and provides storage services from its West Virginia natural gas storage facility.

Columbia plans to file its application for permits for the project with FERC next month. It hopes to have an answer by January next year and start construction in April 2018. The pipelines need approval from the Army Corps of Engineers, the national park Service and FERC.

Monday, February 13, 2017

Coal Ash Bill Goes to the House of Delegates

Last week marked the halfway point of the 2017 Virginia General Assembly session, known as "Crossover." Crossover is when both the House and Senate finish work on legislation originating in that body and pass the legislation to the other body. One of the bills that originated in the Senate, SB 1398, sponsored by state Sen. Scott Surovell, D-36th and Sen. Amanda Chase R-11th titled: Coal combustion residuals unit; closure permit, assessments required, passed the Senate by a vote of 29 to 11 after being amended in committee. The bill moves on to the House of Delegates.

This bill prohibits the Director of the Department of Environmental Quality (DEQ) from issuing a permit for the closure of coal ash pond (technically called “coal combustion residuals unit”) until the Director has reviewed an assessment of closure options prepared by the owner or operator of the coal ash ponds and is a direct response to Dominion Power’s pending closure of their Possum Point, Bremo, and Chesterfield Power Station pending coal ash pond closures. Applacian Power is also closing coal ash ponds at their Glen Lyn, Chesapeake Energy and Clinch River power plants. SB 1398 would require that the owner or operator of the coal ash pond:
  1. Identify and describe any groundwater or surface water pollution located at or caused by the coal ash storage. 
  2. Evaluate the clean closure of the coal ash through excavation and responsible recycling or reuse of coal ash.
  3. Evaluate the clean closure of the coal ash through the excavation and removal of the coal ash residuals to a dry, lined storage in an appropriately permitted and monitored landfill, including an analysis of the impact that any responsible recycling or reuse options would have on such excavation and removal.
  4. Demonstrate the long-term safety of the coal ash storage, addressing any long-term risks posed by the proposed closure plan and siting.
The coal ash is the byproduct of burning coal to make electricity. The U.S. Environmental Protection Agency (EPA) has determined that coal ash is solid waste, not hazardous waste tough it contains heavy metals, including lead, arsenic, boron, selenium and hexavalent chromium. The EPA finalized regulations in 2016 for coal ash storage. The finalized EPA regulation for coal ash requires that coal ash disposal site must have protective liners to prevent groundwater contamination. The rule also requires companies to conduct monitoring of disposal sites, clean up any existing contamination, and close and remediate unlined disposal sites that have polluted groundwater. Finally, monitoring data, corrective action reports, and other important information about the site must be made available to the public.

Possum Point in Prince William County is the first power plant in Virginia to apply for a solid waste permit to permanently close the coal ash ponds on site. Dominion used coal to fire the turbines for the Possum Point, Power Station located on the banks of Quantico Creek and the Potomac River, from about 1948 to 2003. There were 5 coal ash ponds on site: A-E. Coal ash Ponds A, B, and C are currently being decommissioned. One million cubic yards of coal ash from those ponds was moved into Pond D, a 120-acre pond that already contained 2.6 million cubic yards of coal ash. Coal ash Pond E is being decommissioned and was replaced with a water treatment system that began operation this past summer. Dominion Power is proceeding with a plan to “close in place” the 3.7 million cubic yards of coal ash by consolidating and dewatering the coal ash into a coal ash pond they claim is lined, but the adequacy and effectiveness of the old clay liner has been questioned since they proposed this plan.

Once the consolidation and dewatering are completed, the coal ash pond will be capped with an impermeable membrane to prevent infiltration of rain in the future. These old coal ash ponds have been open to the elements and taking on water for decades as well as being in contact with shallow groundwater as was disclosed in the permit applications and modifications. Dominion’s closure plan should have included additional site investigation to demonstrate to the stakeholders in the community that the liner in coal ash Pond D is sound.

The public, environmental groups, county supervisors and state Senators and Delegates have voice concerns. Many are well founded, but still the process of obtaining permits for the closure was far from satisfactory to most stakeholders; disjointed and unresponsive. If you recall last fall Dominion Power agreed to install additional groundwater monitoring wells and conduct bi-weekly monitoring of the new wells. This brought the total number of monitoring wells to 24 and provided enhanced monitoring and protection for Quantico Creek, the upstream neighbors and the Potomac River from the dewatering of the coal ash ponds at Dominion’s Possum Point Power Station.

The recent sampling of those wells showed elevated levels of boron, chloride, cobalt, nickel, sulfate and zinc upstream of the ponds. The new sampling results were inconsistent with the model of the geology and groundwater in the area that Dominion has used in their permit applications. Groundwater often surprises you. Though, Dominion maintains that there is no evidence that its ash ponds have contaminated drinking water wells near the site, they have announced that they will pay for the homes near the Possum Point Power Plant to be hooked up to the Prince William County Public Service Authority water or receive water filtration systems. Offering the neighbors peace of mind and a safe source of drinking water is the right thing to do.

In addition it is essential that testing of groundwater, surface water sediments, and the water treated at the outfalls should have been done for a broader spectrum of contaminants to better protect the environment and determine the extent of impact if any from the decades storage of the coal ash on site. Though Possum Point is downstream from nearby drinking water supplies and is unlikely to impact local residents beyond what has already taken place over the decades; however, the current level of impact needs to be investigated and monitored for the environment and potential potable uses of the groundwater.

It is possible that trace contaminants including metals (and potentially hexavalent chromium) in the coal ash have already leached into the groundwater, Quantico Creek and Potomac from the coal ash ponds. Permanently disposing of the coal ash on site, when properly done, can be protective of the environment and water resources, but requires an effective liner and cap separating the coal ash from the groundwater and rain in addition to ongoing monitoring and maintenance. All physical barriers fail over time this is addressed by the monitoring and maintaining the systems. Moving coal ash to another site for disposal, could potentially risk groundwater at another location unless the landfill monitors their site for the traces of metals that are common constituents of the coal ash. I have always believed that Dominion Power should have relined the pond at the beginning of this process, provided public water hookups for the residents and expanded monitoring. Now the Generally Assembly may step in.

Thursday, February 9, 2017

Water Safety and WSSC

The safety of drinking water is one of the most important public health issues in the United States and any society. For most of the 20th century efforts to achieve safety and to meet drinking water quality regulations have focus on the water filtration and treatment. It was felt that with reliable treatment, any deterioration in source water quality could be overcome. Unfortunately, this has proven not to be true. Variations in water quality have undermined the ability of even advanced water treatment plants to consistently and effectively control water quality and treatment and provide safe drinking water. Additionally, some unrecognized contaminants in trace amounts, may pass through the treatment plant. Thus a need for source water quality protection as an additional “barrier” to contamination and an enhancement to water quality.

The rain and snow melt moves through the watershed into streams and rivers and picks up contaminants along the way. As the water travels over the land surface or through the ground on its way to the rivers, it dissolves naturally occurring minerals and vegetation (organic matter) as part of the natural process. The water can also can pick up pesticides, herbicides and other synthetic/volatile organic chemicals from agricultural land, golf courses, or residential and urban lands.

The Washington Suburban Sanitary Commission (WSSC) the water company for Montgomery and Prince Georges Counties in Maryland, obtain their raw water from the Patuxent and Potomac rivers and then treat the water in their Patuxent Water Filtration Plant and Potomac Water Filtration Plant. Potential sources of contamination in the Patuxent Reservoirs watershed include transportation, petroleum pipelines, agriculture, onsite septic systems, developed areas, and minor permitted discharges. Phosphorus runoff from urban/suburban and agricultural land uses is reported by the WSSC to be the primary contaminant of concern for this watershed. Potential sources of contamination in the Potomac River watershed also include runoff from urban and agricultural land uses, and potential spills from highways and petroleum pipelines. Contaminants of particular concern include natural organic matter and disinfection byproduct (DBP) precursors, pathogenic microorganisms (Cryptosporidium, Giardia, fecal coliform), taste and odor-causing compounds, ammonia, sediment/turbidity and algae.

Water drawn from protected areas of the Potomac and Patuxent rivers is treated in the water filtration plants and is continuously and thoroughly tested, before being sent to homes and businesses through the 5,600 miles of distribution pipes in the WSSC system. Continuous monitoring allows WSSC to respond to changing water conditions to maintain water quality. In the filtration plants water is treated first with coagulation and flocculation (to make small particles and microorganisms in the raw source water adhere to each other); sedimentation (to remove most of those particles and microorganisms); filtration (to remove nearly all the remaining particles and microorganisms); chlorination (for disinfection); lime addition (to minimize the potential for dissolving lead solder used in older homes and laterals lines); and fluoridation. Orthophosphate is also added to help minimize lead corrosion and copper pipe pinhole leaks in home plumbing by creating a protective film in pipes.
from WSSC
Cryptosporidium is a microbial pathogen found in surface water throughout the U.S. Cryptosporidium must be ingested to cause disease, and it may be spread through means other than drinking water. Ingestion of Cryptosporidium may cause cryptosporidiosis, an abdominal infection and may even cause death in the vulnerable. The is just completing a 2 year monitoring program for Cryptosporidium as required by the EPA. Though, WSSC has not reported a problem with Cryptosporidium, they have installed UV disinfection at the Potomac Plant to provide an extra barrier of protection against Cryptosporidium.  

To ensure that tap water is safe to drink, EPA prescribes regulations, which limit the amount of certain contaminants in water that public water systems provide. The Safe Drinking Water Act regulates almost 90 substance. The quality of the water being produced at WSSC is excellent. It meets or exceeds all United States Environmental Protection Agency (US EPA) standards and requirements. The water quality report release at the end of 2016 covers the sampling done during calendar year 2015. There were no violations of the U.S. EPA’s Safe Drinking Water Act for the and you can view the report at this link.

Monday, February 6, 2017

Fairfax How’s Your Water

For those of you who live in Fairfax County and are on public water you receive your water from Fairfax Water. The raw (untreated) water comes from two sources: the Potomac River and the Occoquan Reservoir. The Occoquan Reservoir is fed by the Occoquan River which in turn receives the treated discharge of the Upper Occoquan Sewage Authority treatment plant. The Upper Occoquan Sewage Authority treatment plant is located south of Centreville and west of Route 123 with its discharge pipe upstream of the Occoquan Reservoir so, much of the flow into the reservoir is recycled sewage. In addition, the reservoir receives stormwater runoff from Loudoun, Fairfax, Fauquier, and Prince William counties through the streams and creeks that feed the Occoquan River.

Fairfax Water provides their customers with water treated at one or two of four possible treatment plants. The James J. Corbalis Jr. and the Frederick P. Griffith Jr. Treatment Plants are owned and operated by Fairfax Water and provide water to most of the county. The Dalecarlia and McMillan Treatment Plants, part of the Washington Aqueduct, are owned and operated by the U.S. Army Corps of Engineers and provides water to the City of Falls Church and some of the surrounding area. The Corbalis Treatment Plant and the Dalecarlia and McMillan Treatment Plants treat water from the Potomac River. The Frederick P. Griffith Jr. Treatment Plant treats water from the Occoquan Reservoir. As can be seen below most of the county is served by the Fairfax Water owned water treatment plants- the blue area. 

After World War II Fairfax County had over 20 small water systems that primarily operated water distribution systems. In 1957, the county supervisors created the Fairfax County Water Authority (now called Fairfax Water), to centralize the water supply, but the county did not yet have a reliable water supply and distribution system. The City of Falls Church was supplied water by the Washington Aqueduct. In 1959, Fairfax County Water Authority and the City of Falls Church signed a 30-year agreement allowing the city to deliver water to customers who were located outside the city limits in the county.

Over the years as the county grew Fairfax Water expanded its infrastructure. They built the James J. Corbalis Jr. and the Frederick P. Griffith Jr. Treatment Plants and expanded their distribution system serving over 1.7 million people with the lowest water rates in the region. Meanwhile, the City of Falls Church system (the green and brown areas) provided water to 120,000 people and was using inflated water rates to fund part of the city’s operations. In 2010 a state judge ruled that Falls Church's transfer of water utility profits to their General Fund was an unconstitutional tax on people who lived outside the boundaries of the city. The decision blocked all future transfers, and after appeals, mediation and action by the county supervisors resulted in an agreement for Falls Church to sell its water system to Fairfax County which was ratified by the voters in 2013. The deal required that the high city water rates be lowered to county levels within two years.

The result is that now Fairfax Water provides water to county residents from their two water treatment plants and buy water from the Washington Aqueduct to supply residents in and around the City of Falls Church. The newer developments around Merrifield and the Dunn Loring Metro Station are supplied water from the Fairfax Water owned plants. Water rates and hookup charges throughout the county are now level and undoubtedly, Fairfax Water will provide any expanded water service from their own water treatment plants. Though, both the Washington Aqueduct and Fairfax Water run excellent water treatment plants.

In order to ensure that tap water is safe to drink, the EPA limits the amount of certain contaminants (a list of more than 90 contaminants) that can be in the water provided by public water systems under the Safe Drinking Water Act. When untreated water enters the treatment plants, coagulants are added to cause small particles to adhere to one another and settle in a sedimentation basin. The water is then filtered through activated carbon and sand to remove remaining fine particles. This produces water with extremely low turbidity and provides excellent barrier against pathogens such as Cryptosporidium and Giardia. Next, the water is disinfected with chlorine to kill harmful bacteria and viruses. A corrosion inhibitor is added to help prevent leaching of lead and copper that might be in household plumbing or service laterals. Fluoride is added to protect teeth. Powdered activated carbon and potassium permanganate may also be added to the treatment process to remove taste or odor-causing compounds. In addition to these treatment steps, the Corbalis and Griffith plants use ozone to further reduce odors and organic material.

The quality of the water being produced at Washington Aqueduct and Fairfax Water is excellent. It meets or exceeds all United States Environmental Protection Agency (US EPA) standards and requirements. The water quality report release at the end of 2016 covers the sampling done during calendar year 2015. There were no violations of the U.S. EPA’s Safe Drinking Water Act and you can view the report at this link.

Thursday, February 2, 2017

2016 Generally a Warm Wet Year

from NOAA

In 2016, the main land of the United States average temperature was 54.9°F, 2.9°F above the 20th century average. This was the second warmest year recorded for the mainland, behind 2012 when the annual average temperature was 55.3°F. The last year with a below-average temperature was 1996.

This year started with one of the strongest El Niños on record ushering in Pacific moisture and some much needed drought relief to parts of the West. High elevation snowpack and valley rains hit the west and by late winter 2016 the snowpack across the region were near to and above average. While above-normal precipitation was common across the West, it generally fell short of values often observed during strong El Niño winters.

Regardless, the regional drought footprint did contract, from 45.2 % at the beginning of the year to 21.5% by the end of the year. A strong and persistent ridge in the West limited the number of storms that reached central and southern California where drought conditions were worst. The abnormal warmth of the El Niño in the late winter/early spring period prematurely melted some of the early season snowpack gains across the Sierra. Therefore, exceptional drought conditions remained throughout the year much of the West, and California. It took into this winter for most of California to recover from the drought of the last 5 years and much of southern California remains abnormally dry, yet.

Precipitation also saw regional extremes in the rest of the country. As is typical with a strong El Niño episode, precipitation across much of the West was above normal for the year. California’s precipitation was 3.27 inches above the 20th century average and Washington state’s precipitation was 7.36 inches above average. Several Upper Midwest states were much wetter than normal for the year. Both Minnesota and Wisconsin had their second wettest year on record while the northeast and much of the south (that missed the fall flooding) were dry. 

Generally speaking, precipitation was above average for much of the mainland of the United States west of the Mississippi, while drier-than-average conditions existed for much of the Southeast and Northeast. Locally, the recent rains have provided a pattern of steady but slow drought recovery in the Northeast and Mid Atlantic for the last couple of months. Less than 1% of Virginia remains in drought and the U.S. groundwater monitoring well up the road from my house has recovered to normal levels after recording two of the lowest levels in its 85 year history last fall.

I participate in a citizen science project that measures precipitation in the United States.