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Virginia’s Natural Resources Education Guide 95.
ters. Some of the precipitation filters into the soil and continues down through cracks and crevices to replenish ground water, a zone where all pore spaces become saturated.
River Basins Virginia has nine major river basins whose natural, recreational, commercial, and cultural resources com- bine to make the Commonwealth a rich blend of colors and contours. While most of the state drains into the Chesapeake Bay, water from the westernmost basins ends up in the Gulf of Mexico. Rivers in the Roanoke and Chowan basins, by contrast, empty directly into the Atlantic Ocean. It was along the banks of the wide, placid James River that English colonists settled in the early 1600s, establishing Tidewater Virginia as the “Cradle of the Republic.” The James and her sister rivers draining to the Chesapeake Bay — the York, Rappahannock, and Potomac rivers — drain nearly two-thirds of Virginia’s land mass.
Virginia’s Water ResourcesVirginia’s Water ResourcesVirginia’s Water ResourcesVirginia’s Water ResourcesVirginia’s Water Resources
Water is vital to Virginia’s well-being, as it is to com- munities across the globe. Water supports virtually every human endeavor—from farming and forestry to the generation of electric power and all types of manufacturing processes. Water sustains human “habitat” as it does for the millions of plants and animals that share the planet with us. Here in our little corner of the world, fresh water use currently totals more than 5,467 million gallons per day (mgd), or approximately 826 gallons daily for each Virginia resident.
Where is Virginia’s Water? The state’s average annual rainfall is 42 inches but, in truth, it ranges from 35 to 55 inches (based on 30- year records). In Virginia, rainfall is distributed evenly throughout the year without distinct wet and dry pe- riods. This abundancy — approximately 79,800 mil- lion gallons per day — supplies Virginia’s surface and ground water. Precipitation in the form of rain, snow, or ice falls to the earth and replenishes surface wa-
(Year 1985; in million gallons per day)
Virginia’s Water Budget Analysis
Hydrologic Cycle and Water Budget
INFLOW: Precipitation 79, Surface water inflow 1, 81,
OUTFLOW: Evapotranspiration 52, Surface water outflow 28, 81,
Source:Water Atlas of Virginia, © Tennyson Press, Lexington, Virginia, 1994. Reprinted by permission.
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runoff and disastrous flooding. Water levels in the James River in Richmond reached a peak of 36. feet, the highest recorded level in more than 200 years. Average stream flow at this station is 6, cubic feet per second (cfs) and, during Agnes, it peaked at 313,000 cfs. Water supply, sewage treatment, and electric and gas plants were flooded. Throughout the state, 1,400 homes, roads, and bridges were destroyed and 13 people killed, amounting to 325 million dol- lars in damage.
Protecting Water Resources Protecting our water is the responsibility of all Vir- ginians, including state government. Virginia was among the first state in the nation to embrace this responsibility and in 1946 enacted the Virginia Wa- ter Control Law to combat water pollution (two years before the adoption of the first Federal Water Pollu- tion Control Act by Congress). Over the past 30 years, resource managers have made great strides to address water-related concerns. One concern is adequate future supplies for shared use by consumers, farmers, industries, and recreationists. The goal sounds simple enough but may prove our most challenging: to provide the right quantity of satisfactory quality water where and when it is needed. For example, power plants supplying electricity and factories supplying goods use vast amounts of water.
The Commonwealth’s western rivers—the ancient New River and the Tennessee-Big Sandy—course through rugged mountain valleys where generations of Virginia farmers, miners, trout fishermen, and white- water rafters have capitalized on their spirit. And the Roanoke and Chowan rivers meander through Virginia’s Southside, sustaining peanut and tobacco farms, textile industries, and lakeside vacationers. Rivers carry enormous amounts of water, es- pecially during floods when peak flows can reach 40 to 80 times their average volumes. During such events, rivers also transport enormous amounts of sediment and pollution. And rivers are known to unleash tre- mendous force upon human resources during such storm events. It wasn’t that long ago, in June 1972, that Hurri- cane Agnes deposited more than 6 inches of rain over many parts of Virginia (a record amount in one day for Lynchburg and the National Air- port in Washing- ton, DC). The soil was already satu- rated and when heavy rains hit, the result was rapid
Electric Power Industry 66%
Who consumes what?
domestic Use^ Rural/ 3%
& MiningIndustry 14%
Supplies - 17%Public Water
98.0 Virginia Resource-Use Education Council
farms, streets, parking lots, lawns, construction sites and other developed lands. Indeed, the April 1996 assessment found that the vast majority (83 percent) of water pollution problems in the Commonwealth are caused by such elusive sources. Runoff often carries excess fertilizers, manures, toxic chemicals, pathogens and sediments into rivers and streams.
Here are some suggestions on how to “lighten your footsteps” upon the land: t Farmers, foresters, and contractors engaged in land- altering activites can take sediment and erosion con- trol measures; t Localities can implement storm water controls and steer development away from sensitive natural areas; t Homeowners can use less toxics in the home and garden—specifically, cleansers and pesticides; t Homeowners and developers can reduce paved (im- pervious) surfaces and the use of fertilizers; and t Everyone can recycle motor oil and dispose of haz- ardous substances safely by following label instruc- tions.
DEQ and other state agencies are working with local governments, industries, volunteer groups, and citizens to address these and other water pollution issues. Today DEQ maintains a network of more than 1,100 monitoring stations that regularly sample and analyze streams, rivers, lakes, and bays across the state. DEQ monitors 17,000 miles of free-flowing streams. The agency also regularly surveys stream life — the aquatic organisms living in the water — and takes samples of bottom sediments and fish tissues for
toxic analysis. Together with data from other state agencies and active citizen monitoring groups, DEQ has a comprehensive database of water quality infor- mation, the basis for making continued improvements and informed decisions.
Fundamental Learnings Related to Water Resources R All life processes, from the level of a cell to that of an ecosystem, require water. Both the quantity and quality of water are important. Habitats with abundant plants and animals are areas with clean water in good supply. R Water is found in the atmosphere, on the surface, and underground. The water cycle is central to life on Earth and connects Earth systems. R Water is a natural resource that must be managed. The amount of available freshwater is limited (99% of the Earth’s water is saline) and must support multiple users. Clean, sustainable water supplies are vital. When supplies fail to meet demands, conflicts arise. R Aquatic environments are subject to much use and abuse by people. Water pollution occurs when chemicals, nutrients, or sediments are placed into water faster than they can be removed by natural processes. Water pollution can often be traced to runoff in the watershed. R While water is useful as a cleaning agent (“the universal solvent”) and as a means for disposing of soluble waste, the capacity for water to dilute pollutants is limited.
Additional Resources Web Sites: u Virginia Department of Environmental Quality; www.deq.state.va.us u Va. Department of Conservation & Recreation; www.dcr.state.va.us Other Resources: u van der Leeden, Fritz. 1993. Water Altas of Virginia, Basic Facts About Virginia’s Water Resources. Lexing- ton, VA: Tennyson Press, ISBN: 0-9638711-0-2. A collection of 46 maps depicting various aspects of Virginia’s water resources accompanied by an expla- nation of key features; call (540) 463-2599. u Citizens for Water Quality; a state-wide consor- tium of people interested in preserving and enhanc- ing Virginia’s water resources; contact the state water quality coordinator at DEQ, (804) 698-4026.
Interested in a Water Quality Project?
Students can participate in a number of projects. Here are a few ideas: ! Stream and Beach Clean-ups - involve riverbank or beach trash collection; ! Tree Plantings - involve planting trees in the “riparian” zone, or streambank corridor; ! SAV Counts and Plantings - involve restoration of underwater vegetation; and ! Water Quality Monitoring - involves a class to become trained in biological or chemical monitoring.
Virginia’s Natural Resources Education Guide 99.
Grade Levels: 3-
Science SOLs: 3.9, 4.8, 6.
Materials: rrrrr A map of your local area show- ing streams (topographic is good but not essential) rrrrr Paper and markers rrrrr Paint trays (1-2) rrrrr Aluminum foil, or a white shower curtain rrrrr Rocks, or blocks rrrrr A powdered “pollutant,” such as cinnamon or Kool Aid or cocoa rrrrr Sponges and small toys
Objectives: Students will be able to predict where water will flow in water- sheds, describe drainage patterns in watersheds, and identify sources of pollution.
Vocabulary Words: erosion groundwater hydrologic cycle nonpoint source pollution nutrients pollutants runoff water pollution watershed
What’s Your Watershed Address?
Easy ways to demonstrate how water flows through a watershed
Watershed Background A watershed, also called a drainage basin, is a geographic area in which water, sediments, dissolved minerals and other pollutants, including trash, drain into a common body of water. While we all reside in one, many of us do not even know its name. There are nine distinct watersheds or river basins that lie within the state of Virginia. They are from south-west to north-east: The Tennessee-Big Sandy, the New, the Roanoke, the Chowan, the James, the Potomac-Shenandoah, the Rappahannock and the York. The James River is the largest watershed. It includes all or parts of 39 counties and 18 cities and drains one-fourth of the state’s land area into the Chesa- peake Bay. Discuss the concept of a watershed and how water travels over and through the land. Students may wonder where water goes after it flows down the street during a heavy rainstorm. Make the connection between people living in the watershed and the impacts that they have upon water quality; specifically, non-point source pollution. Provide some examples of how the actions and behaviors of individuals (including pets and their owners) and businesses in your area affect the water quality of your local watershed and the body of water into which the watershed drains, such as the Chesapeake Bay. Don’t forget to include sewage treatment plants, homes, commercial developments, and factories. Discuss the speed at which water flows and how moving water changes the land. You can refer to the branches on a tree, or the veins in a leaf, or the human nervous system to describe how bodies of water “branch out” with smaller branches analogous to streams branching into larger ones, such as rivers, and so forth. Explain that watersheds can be open or closed depend- ing on where the water drains. In closed systems, there is no outlet for the water, so it leaves the system naturally by evaporation or by seeping into the ground (becoming groundwater). In open watershed systems, such as those found in Virginia, water eventually flows into outlet rivers or a bay and, ultimately, the sea.
Activities There are numerous ways that students can build a model of a watershed, ranging from individually constructed models made of paper to larger scale models created by using a shower curtain or tarp. Here are some easy ways to demonstrate topography and the action of water flowing through a water- shed:
- Students use crumpled paper to create a miniature watershed model: Crumple a piece of paper into a tight ball. Gently open up the paper, but don’t flatten
Virginia’s
Water Budget Analysis
(Year 1985; in million gallons per day)
INFLOW: Precipitation 79, Surface water inflow 1, 81,
OUTFLOW: Evapotranspiration 52, Surface water outflow 28,
Hydrologic Cycle and Water Budget
Source: “The Water Atlas of Virginia,” © Tennyson Press, Lexington, Virginia, 1994. Reprinted by permission.
