On a random day last week I took a look at the online USGS stream gauge on the Rappahannock River near Fredericksburg VA. My intention was to get a typical flow number to make a quick calculation. However, the flow on that day was at 11% of normal. That stopped me in my tracks. That meant that at that moment the flow of the Rappahannock River was about 142 million gallons/day.
The Rappahannock River headwaters are in the Piedmont, fed
by rainfall and snowmelt. The Rapidan, Robinson and Hedgeman rivers all come
together and connect with the Rappahannock about 10 miles northwest of
Fredericksburg. The river is subject to seasonal variations in flow, with
higher levels in the spring due to snowmelt and rainfall and lower levels in
the summer due to decreased rainfall, but this summer’s flow reduction seems very
extreme. Even in Piedmont, the drought was only moderate in a portion of
Fauquier County.
The Rappahannock River’s upper reaches, from the headwaters
to Mayfield Bridge in Fredericksburg, are designated a Virginia State Scenic
River. In addition to being one of Virginia’s top destinations for fishing, the
river is a favorite for outdoor recreation on and off the water along the unspoiled
river corridor. The river has been free flowing since the Embrey Dam was breached.
The Dam was constructed in 1910, replacing a type of earth and timber dam
called a crib dam that was built in 1853. The dam at one time provided water to
a Virginia Electric Power Company’s hydraulic power station. The dam made the
Rappahannock River impassible above Fredericksburg to spawning fish. With the
dedicated work of Friends of the Rappahannock and Senator Warner, and a federal
grant the dam was removed in 2004. allowing migratory fish like American shad
and striped bass gained access to spawning grounds in the upper Rappahannock
and its tributaries.
Today, much of the river’s watershed is rural and forested
but is facing increasing pressure from development and population growth and a
new challenge-data centers. Back in the day counties and cities used to submit water-supply plans to the state every
10 years, but that’s changed to regional planning, and there are five different
water planning regions in the Rappahannock watershed with none of them
coordinating with each other. The relatively recent increase in development in
the suburbs southeast of Washington D.C. and the rapid expansion of data centers
and planned data centers into Fauquier, Spotsylvania, King George and
Caroline Counties all wanting to stick a straw into the river to supply the 1-5
million gallons of water a day those massive industrial buildings need to
operate could challenge the river and farming’s survival in the region.
Even before data centers Caroline and King George counties
had water troubles. By the early 2000’s it became clear that the Potomac
Aquifer that the counties depend on for potable water was beginning to fail. Caroline
and King George counties are within the current groundwater management areas of
Eastern Virginia and Eastern Shore which were created by the DEQ to curb
withdrawals from the aquifer’s biggest users. However, it has failed to
preserve that resource for those counties.
Over half of reported groundwater withdrawals in Virginia are
located within the groundwater management areas and are permitted. Despite all
the efforts by DEQ, the groundwater level in the Potomac Aquifer has continued
to decrease due to the historic over allocation of the water that has resulted in a deterioration
in both water quality and quantity in Caroline and King George counties. Despite
DEQ reducing permit limits by 52% the groundwater aquifer cannot long support
growth in Caroline and King George counties and they have been forced to look
to the Rappahannock River for water. The problems is that the Rappahannock River
is not unlimited and that accessing surface water requires much more water
infrastructure and that costs money.
Caroline County wants to build a water-intake facility that could withdraw up to 13.9 million gallons of water a day from the river, treat that water then, build the pipelines that would carry the water across the county for some residential and business growth, but mainly for the industrial projects proposed in Carmel Church and Ladysmith. King George County has been considering different approaches to tapping the Rappahannock River.
The King George Board of Supervisors recently approved rezoning to build 19 data centers for Birchwood Power Partners, which presented the plan on behalf of Amazon Web Services. The Birchwood site already has a permit to withdraw water from the river, dating from when it was an operating coal-fired power plant. The residual cooling water from the data centers would be treated and returned to the Rappahannock however it is unclear the salinity limits and treatment parameters that would be applied and if the permit would have to be reapplied for. Amazon plans $35 billion investment to establish data center campuses throughout Virginia by the year 2040.
So, back to the flow of the Rappahannock River- on that day, at
that spot, the flow of the Rappahannock River was about 142 million
gallons/day. Nineteen data centers use
between 19 and 95 gallons a day of water, Caroline County wants 14 million
gallons a day, and Prince George is talking about 4 million gallons a day. Motts
Drinking water plant is designed to produce up to 24 million gallons a day. Then there is irrigation, ecological need and other users being approved each day. This
summer people walked across the Rappahannock River on rocks revealed when the river
level fell as the river was reduced to puddles and wetlands below Fredericksburg. We need to manage and properly allocate our water resources in a
changing climate and economy to assure that Virginia has a future during both wet years and drought.
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