EVERYONE LIVES IN A WATERSHED
A watershed is an area of land from which all water drains
into a common waterbody. Watersheds come in many shapes and
sizes: hilly, flat, rocky, forested, and marshland.
Watersheds can be quite small, such as a few hundred acres
draining into a small creek, or very large, like the 64,000
square mile drainage basin of the Chesapeake Bay.
A watershed can include a river or the tributaries that
empty into it along its course. Several small watersheds make
up large watersheds, creating a series of watersheds within a
larger area called a drainage basin.
Water enters a watershed through both direct and indirect
means. Precipitation in the form of rain or snow enters
directly as surface runoff or indirectly as water seeping
through the soil via the groundwater system.
Pollution in a Watershed
Events occurring in the smaller watersheds, whether good or
bad, ultimately affect the quality of water that flows into
the larger watershed and into the downstream rivers and
Water is not the only substance to end up in stream systems.
Chemical pollutants, fertilizers, pesticides, trash, and
debris all enter streams with the water draining from the
watershed. These foreign substances come from many sources
and can be detrimental to the health of stream systems by
continually degrading surrounding habitats and the life they
Even if a home is not next to a stream, it is in a
watershed, and common household practices can contribute to
overall pollution entering stream systems. Actions taken
anywhere in a watershed can affect both the quality and
quantity of stream water...and ultimately the water supply.
Land Use in a Watershed
Land use changes are inevitable. However, the rate at which
land use is changing causes problems for the environment,
specifically stream water quality.
Urban development increases impervious surface (rooftops,
roads, driveways, sidewalks, and parking lots), which leads
to more stormwater runoff. More runoff entering streams
changes the natural ecosystem. Unless stormwater management,
erosion control strategies, and riparian
zone management are carefully considered in the watershed
plan, degradation can be expected.
Careful planning that takes into consideration the location
and design of man-made structures is essential. Planning for
a new building or road must include plans for stormwater
runoff control, maintenance of riparian buffer zones, and
location of wetlands and upland forests.
Development should not necessarily be stopped, but its
potential harm to local streams should be minimized. Local
governments should encourage developers to practice proper
stewardship of land and streams when development occurs
within a watershed. The entire watershed must be viewed as a
whole ecosystem; unbalance in one part adversely affects
Managing the Watershed
Land uses preventing soil erosion, heavy runoff of
stormwater, and pollutants characterize a well-managed
watershed. On the other hand, overgrazing, overuse, improper
management of agricultural land, uncontrolled urban runoff,
and mismanaged urban development sites characterize abused
Watersheds are an integral component of a healthy
ecosystem—one that sustains water quality suitable for fish,
waterfowl, and other aquatic life, and of course for
swimming, fishing, and human consumption. Taking care of
streams and rivers is an important part of cleaning up the
environment and preserving the land and water for future
Make a Difference
Factor in the cost of lost habitat when establishing the
cost/benefit analysis for development.
Maintain buffer zones on both sides of streams sufficient
in area to accommodate the volume of water delivered during
Restore and maintain wetlands. Wetlands act as filtration
and flood control mechanisms.
Use permeable paving materials that allow rain to penetrate
the surface rather than running off directly into a stream.
Maintain natural vegetation as much as possible. A sapling
cannot replace benefits of a mature tree.
Control soil erosion on development sites.
Promote an environmentally friendly setting by restoring
damaged areas, maintaining the quality of streams, and
WATER CONSERVATION IS EVERYONE'S JOB
Water supplies in the Northern Virginia area are more than
adequate to meet current needs, but it may not be that way in
the future. This valuable resource must be conserved and
Conservation Saves Money
Conserving water can mean substantial savings in sewer,
energy, and water bills. For homeowners with septic systems,
conserving water reduces wear and tear on the system and
requires less energy for pumping well water.
Widespread reduction in water use can also mean a reduced
need for new or expanded sewer treatment facilities. Tax
dollars saved by not expanding existing facilities could be
used to improve water treatment techniques.
Facts About Earth's Water
Approximately 80% of the Earth's surface is covered with
Earth has the same amount of water as when the planet was
Only one percent of the Earth's water is usable fresh
water. The remainder is salt water (97%) and water frozen
in glaciers (2%).
Nature recycles water in an endless cycle.
The water consumed today may have been a drink for a
The average person uses 100 gallons of water a day.
In 1995 (most recent year for which figures are available)
the United States used more than 36 trillion gallons of
More than 50% of wetlands that recharge and purify
groundwater have been destroyed in the United States.
Earth will not get any more water.
Make a Difference
Use low flow faucets and showerheads, reduced flow toilet
flushing equipment, and water saving dish and clothes
Check for water leaks. If the water meter dial moves while
no water is being used, there is a leak.
Take short showers instead of full tub baths. Avoid letting
faucets run unnecessarily.
Only use fully loaded dish and clothes washers.
Install a rain barrel
or cistern to capture rain water for reuse.
Wash cars only when necessary. Use a bucket and a spray
nozzle to save water.
Go to a commercial car wash that
uses water efficiently and disposes of runoff properly.
Water lawns at the coolest part of the day to avoid
evaporation. Use slow watering techniques such as trickle
irrigation or a soaker hose.
Use mulch to hold in soil moisture.
Do not over-water lawns or gardens.
EARTH DEPENDS ON GOOD WATER QUALITY
The water in stream systems is used several times before it
reaches the ocean. People drink it, cook with it, bathe in
it, and swim in it. Farmers use water in food production, and
businesses use it in commerce. Water supports fish, wildlife,
and recreation, and creates an aesthetically pleasing
With all of its uses, the need for good water quality is
imperative. Good quality water contains sufficiently high
physical, chemical, and biological properties to sustain all
of its uses.
Water quality is a reflection of a body of water's
composition as natural processes and human activities affect
it. Water quality has many different definitions. For an
ecological scientist it means a balanced and properly
functioning aquatic ecosystem; for a public health official
it means clean, clear, drinkable water; and for a local
fisherman, it means the quality and quantity of fish.
Pollution is an undesirable change in the physical,
chemical, or biological characteristics of air, land, or
water that adversely affects the living conditions for either
humans or other living organisms. Water pollution is the
adverse and unreasonable impairment of the beneficial uses of
Water quality can be disrupted by direct and indirect
sources. Direct sources are fairly obvious and include such
practices as dumping waste and hazardous pollutants into
streams. Indirect sources are called nonpoint source (NPS)
pollution. Stormwater runoff, which may contain
fertilizers and pesticides, soil lost from development sites,
and oil residue washed off streets, is NPS pollution. This
type of pollution is much more difficult to pinpoint and
Make a Difference
Practice water conservation. Use less!
Stop nonpoint source pollution in backyards by using
appropriate lawn care techniques.
Limit use of pesticides and fertilizer. Use them at
appropriate times of the year in recommended amounts.
Prevent property erosion. Cover bare soil with vegetation
Encourage local government to make water quality
improvements a high priority.
Encourage environmentally friendly development in the
Participate in a stream cleanup program.
Learn to recognize water quality problems in local streams.
Bring water quality problems to the attention of the proper
WATER POLLUTION'S CAUSES AND EFFECTS
Water pollution is an overabundance of one or more natural
or man-made substances in a body of water. Sources of natural
pollutants include sulfur from soils, iron deposits, residue
from volcanic springs, calcium, and tannic acid and methane
gas from marshlands. The two major types of man-made
pollutants are point source pollution and nonpoint source
Point Source Pollution
Point source pollution comes from a single source, such as a
pipe, culvert, or ditch. Point source pollution is commonly
associated with industrial sites, waste water outflow pipes,
or sewage treatment plants. The signs of pollution that most
people can identify are discharges of multicolored liquids
from pipes, algae growth in a stream resulting from sewage
outfall discharges, smoke from smokestacks, and refuse dumps.
Nonpoint Source Pollution
NPS pollution presents a more subtle water quality problem
because it originates from widely dispersed and diverse
sources, not a single outlet. Natural forces such as rain or
wind often play a key role in transporting pollutants to
stream systems. Examples of NPS pollution are soil from
eroded fields and development sites; chlorinated swimming
pool water drained into storm sewers or directly to streams;
runoff from backyards containing fertilizers and pesticides;
pet wastes, motor oil, paint thinner, or antifreeze dumped in
storm sewers; and motor oil and other substances that wash
off streets and parking lots.
Point source pollution has been controlled during the last
50 years through wastewater treatment, air scrubbers, and
filtration devices. The cleanup of municipal and industrial
sources has resulted in the remarkable improvement of water
quality in streams.
One example is the Potomac River, which until recently was
considered a polluted river. The control of point source
pollutants has contributed to the revival of the Potomac and
many other major river systems throughout the country.
There is still a long way to go. Significant sources of
pollution continue to enter streams, and NPS pollution is the
major culprit, accounting for more than 50% of nutrients
reaching the Chesapeake Bay.
Make a Difference
Start at home and in the yard.
Fertilize according to soil test results.
Apply pesticides according to instructions on the label.
Maintain septic systems.
Recycle grass clippings and leaves by mulching or
Recycle used motor oil.
Collect litter and animal waste.
Drain pools on a large expanse of grass to dissipate
chlorine and allow water to filter through soil.
Control soil erosion by seeding grass, installing sod, or
planting ground cover to protect bare areas.
Direct roof water onto grassy areas.
Use porous surfaces such as flagstone or gravel, rather
than asphalt or concrete.
Dispose of household hazardous waste properly. Never pour
paint, antifreeze, motor oil, cleaners, or solvents down
drains inside or outside the home.
LOOKING CLOSER AT NPS POLLUTION
How NPS Pollution Occurs
With rain, no matter the amount, comes serious pollution
washing from the land into lakes, bays, rivers, streams, and
aquifers. Where stormwater cannot soak into the soil, it runs
off, eroding exposed land and filling street gutters.
The onrush of rain water or snowmelt runoff sweeps
accumulated dust, dirt, debris, organic matter, and toxic
pollutants from roads, construction sites, and lawns into
city storm sewer lines and sometimes directly into surface
waters. Farm runoff may channel water muddy with sediment,
fertilizer and pesticide residues, salt, and animal wastes
into streams and larger bodies of water. The adverse impacts
of NPS pollution relate to how close sources are to
waterbodies, land use, type of soil, and slope of the land,
although pollutants from distant sources may reach the same
waterbodies after several storms.
NPS pollution is not restricted to a single area.
Ninety-nine percent of sediment, 88% of nitrates, and 84% of
phosphates entering the United States' lakes and streams are
considered NPS pollution.
Effects of NPS Pollution
Poison fish, aquatic animals, and wildlife.
Cover fish spawning beds, killing fish eggs.
Act as a grinding mechanism on stream beds, destroying
aquatic life residing on the stream bottom—from
macroinvertebrates to fish and reptiles.
Increase decomposition of organic debris, depleting the
oxygen in water that is necessary to support aquatic animal
Fill in streams and reservoirs.
Add nitrates and phosphorous to water causing extensive
algae blooms and the potential death of lakes and
FIVE TYPES OF NPS POLLUTION
Sediment is eroded soil particles. Erosion occurs when rain
or moving water dislodges and carries soil particles, organic
matter, and plant nutrients as it flows. The process of
erosion creates excess sediment. This sediment is considered
an NPS pollutant because it comes from a variety of sources:
cropland, pasture, urban/suburban settings, construction
sites, and sanitary landfills.
The texture of the soil, its potential for absorbing water,
the amount of time it is exposed to water, the steepness and
length of the slope, and the amount of protective cover on
the soil are all factors influencing the extent of erosion.
Disturbed land erodes more easily than land in a natural
Erosion is a natural process. Some erosion is inevitable and
cannot be stopped. However, urban development that disturbs
soil and vegetative cover results in an unnatural
acceleration of the process and can cause water quality
problems, local area flooding, and increased maintenance
Erosion degrades water quality when pollutants, such as
phosphorus, bind to the soil and are carried into waterways
along with runoff. Local area flooding can result from the
eroded soil clogging storm drains and from sediment altering
the depths of local creeks and streams. Erosion-induced
flooding can cause property damage and added maintenance
costs to both the property owner and the agency responsible
for surface water management.
Soil particles resulting from the erosion of land are
carried by rainwater to streams, lakes, rivers, and bays.
Phosphorous, a nutrient, attaches to sediment and is carried
to streams by runoff. Sediments accumulate in waterbodies and
destroy feeding grounds for aquatic life, clog fish gills,
block light, and increase water temperature.
Erosion Hurts Streams
When large quantities of soil enter waterways, pollution
occurs. In terms of sheer volume, sediment is one of the most
devastating pollutants affecting waterways.
Sediment pollution of streams and reservoirs reduces their
volume capacity and increases the expense municipalities and
industries pay to treat water. Millions of dollars are spent
each year dredging channels, harbors, and drainage ditches to
remove excess sediment.
Sediment suspended in water destroys fish and wildlife
habitat. Sediment from eroding stream banks and land surfaces
and agricultural and industrial chemicals carried by that
sediment could smother aquatic life, clog fish gills, and cut
off light to underwater plants. In addition, eroded areas may
be unable to support vegetation. Sediment pollution can be
just as deadly to aquatic life as cyanide or DDT.
Signs of Erosion
Bare spots on lawns or property
Exposed roots of trees and vegetation
Small stones or rocks becoming evident
Soil splashed on windows and exterior walls
Small rills or gullies beginning to show
Buildup of silt in certain areas
Widening and deepening of stream channels
Undercut and fallen trees in stream channels
Make a Difference
Consult a trained professional about structural or
vegetative solutions for controlling erosion.
Remove obstructions from stream channels and revegetate
Establish adequate vegetative cover with appropriate plants
and grasses, especially on all bare spots.
Landscape yards to minimize rainwater runoff.
Preserve neighborhood trees that help minimize the damage
caused by surface runoff.
Control rainfall runoff by diverting water away from
Place retaining walls or diversions on steeply sloping
ground to reduce the rate of water flow and erosion.
Trash and Organic Debris
Leaves, grass clippings, garbage, and animal waste become
part of the runoff entering storm drains and local waterways
and clogging the system. Decaying organic matter depletes
oxygen needed by aquatic life, leaving fish and shellfish to
Trash and organic debris is one of the easiest types of NPS
pollution to control.
Dispose of litter in garbage cans or in recycling bins.
Recycle glass, aluminum, plastic, paper, motor oil, and
newspapers. Compost yard and garden waste. Pick up pet waste
and bag it with regular household trash or flush it in the
toilet. And, never intentionally dump anything into a storm
Nutrients are essential to water life, but too much can harm
more than help. Phosphorous, nitrogen, and potassium are
nutrients that help plants and animals grow. Found in
fertilizer, sewage, detergents, and animal wastes, these
elements are not harmful to the environment in low doses.
However, excess nutrients in an already healthy environment
can be dangerous. Nutrients carried by stormwater runoff from
the land into the water become nonpoint source pollutants.
Too many nutrients can cause an overgrowth of vegetation or
bloom of algae—tiny plants that give water a green to
blue-green color. Eventually the excess plants die and decay.
The decaying process depletes oxygen in the water, leaving
less for aquatic plants and animals. The balance of life in
the stream ecosystem is interrupted and disturbed.
An overgrowth of algae also minimizes the amount of light
that can reach aquatic plants. An increase in dead organic
material from the dying plants exacerbates the problems
associated with low oxygen levels.
The loss of sea grasses in the Chesapeake Bay and its
tributaries is an example of the harmful effects of nutrient
enrichment. Once destroyed, sea grasses do not grow back
Make a Difference
Use fertilizers and pesticides only when necessary and then
at recommended rates. Follow the manufacturer's
instructions for application.
Ensure that animal waste from operations such as dairies,
chicken, hog, and horse operations, feed lots, and catfish
ponds is managed properly.
Make sure septic tanks work properly.
Use low-or no-phosphate detergent.
When operating a boat, be sure to handle trash and
Toxins are chemicals that can cause human and wildlife
health problems. They include organic chemicals and metals,
pesticides, herbicides, formaldehyde, household chemicals,
paint, paint cleaners, gasoline, motor oil, battery acid, and
roadway salt. Toxins accumulate in fish and shellfish either
killing them or making them more susceptible to disease.
Infected fish and shellfish can have a direct impact on
humans in the food chain.
Pesticides—insecticides, herbicides, rodenticides, and
fungicides—are chemicals widely used by farmers, foresters,
exterminators, and homeowners to kill harmful insects and
weeds, to increase crop and timber harvests, and to prevent
the spread of plant, animal, and human parasites and
When improperly applied, pesticides can pollute waters and
poison fish, plants, and animals living in and around water.
Pesticides are considered NPS pollutants because their source
of origin is often difficult to locate. They can migrate
considerable distances via air or water and be released by
rainfall, complicating the process of pinpointing the source.
Although targeted at pests, certain pesticides inadvertently
can harm nontarget organisms—stream insects, fish, wildlife,
domestic animals, and humans.
Alternatives to Toxic Pesticides
Use less toxic pest control products. When used according to
label instructions, insecticidal soap, BT (Bacillus
thuringiensis), milky spore, and dormant oil sprays are
less toxic to the environment than other commercial products.
Integrated Pest Management (IPM) emphasizes frequent
monitoring to assess pest population buildup and the
evaluation of factors, including environmental effects, prior
to pesticide application.
Use natural predators. Introduce animals and insects that
Time plantings. Regulate planting and harvesting to avoid
times when insects are most abundant and damaging.
Do a little hand work. Remove eggs, larvae, cocoons, and
adults from plants by hand.
Use resistant plants. Cultivate plants that are relatively
free of major pests and diseases.
Know the appropriate growing conditions. Make sure the
amount of shade and sunlight, moisture, and pH levels are
appropriate for plants.
Mix plant varieties. A mixed stand of vegetation is less
susceptible to insect damage than single species crops.
Introduce natural pathogens and parasites. Use bacteria,
viruses, and insect parasites to kill pests without harming
Control insect hormones. Prevent an insect from growing
into a sexually mature adult.
Use chemicals only as needed. Smaller amounts and careful
application ensure a healthier environment and better pest
Mulch. Use where appropriate to control weeds.
Rotate plants/crops. Yearly rotation of garden plants
decreases the need for pesticides.
Minimize Pesticide Hazards
Read and follow the label carefully.
Buy only the quantity needed.
Wear any protective clothing specified on the product
Wash hands immediately after application.
Apply only the amount specified on the product label and
only on the plants and areas listed in the instructions
Make sure people and pets are out of the area during
application and until the spray has dried.
Never apply near wells, streams, ponds, or marshes unless
the instructions specifically allow such use.
Never apply to bare soil.
Don't apply if rain is forecast, unless specified on the
label (some pesticides do need to be watered after
Dispose of containers according to label directions.
Choose the least toxic pesticide. Those with the signal
word Caution on the label are considered the least toxic,
whereas the signal word Warning indicates moderate
The presence of bacteria in water, which are normally found
in the intestinal tracts of humans and animals, signal that
disease-causing pathogens may be present. Giardia and
cryptosporidium are pathogens that have been found
occasionally in public-water supplies and have caused illness
in a large number of people in a few locations. Pathogens can
enter our water from leaking septic tanks,
wastewater-treatment discharge, sewer overflows, and animal
waste. Like toxins, pathogens build up in fish and shellfish
killing them or making them susceptible to disease.
Many jurisdictions routinely monitor urban streams to
measure the amounts of bacteria that, although harmless
themselves, have similar sources (animal and human waste) as
do the waterborne pathogens. The harmless bacteria therefore
act as indicators of the possible presence of other bacteria
that are not harmless.
STORM DRAINS ARE NOT TRASH CANS!
Everything that goes into a storm drain, flows out into
neighborhood streams, local lakes and rivers, and eventually
into larger bodies of water such as bays and oceans. Each
time trash, motor oil, litter, pet waste, fertilizer, yard
and garden debris, household chemicals, and road sand and
salt are dumped into or washed into storm drains, aquatic
life is endangered.
However, these nonpoint source pollutants are some of the
easiest to control.
Make a Difference
Never dump anything into a storm drain.
Dispose of trash and litter in the proper garbage or
Recycle motor oil at a local gas station.
Pick up and bag pet waste separately, then dispose of it
with the regular trash or flush it down the toilet.
Use fertilizer sparingly and according to soil test
Compost yard and garden debris.
Dispose of household chemicals according to label
Road sand and salt should be vacuumed up by the proper
transportation authority. If this is not being done, call
the Department of Transportation. Homeowners can help by
sweeping up and disposing of road sand and debris.
Mount a Don't Dump
campaign. Organize neighbors, homeowner or civic
associations, or youth groups to educate the community
about the dangers of dumping into a storm drain. Then
stencil Dumping Pollutes—Drains to Stream on the storm
drains as a reminder.
Remember, storm drains on public streets are owned by the
Department of Transportation or the local homeowner
association and may not be painted without specific
permission. Contact the Northern Virginia Soil and Water
Conservation District for advice on conducting a stenciling
LET'S WORK FOR CLEAN WATER
There are many things that can be done right now to prevent
NPS pollution. Here are some important best management
Have septic systems pumped out and inspected by a licensed
septic tank contractor every three to five years.
Keep cars in good working condition and try to reduce
amounts of driving. Studies show toxic materials and
nitrogen compounds spewed into the air by cars fall back
onto the land where they can be washed into the water.
Compost yard wastes.
Apply fertilizers and pesticides sparingly and use
alternatives when possible.
Fertilize according to soil test results.
Pick up trash, litter, and pet wastes.
Dispose of motor oil, chemicals, and other hazardous waste
Get a conservation plan or
follow an existing one.
Manage manure for maximum crop nutrient value and minimum
Keep livestock out of streams and riparian zones.
Reduce erosion from crop fields by using conservation
practices such as strip cropping, reduced tillage, and crop
Minimize barnyard runoff.
Use rotational grazing systems for pasture.
Leave vegetative buffers along stream banks.
Integrate chemical and biological controls to manage crop
Compost organic yard wastes.
Developers and Contractors
Use porous pavements on low-traffic areas, leave vegetative
buffer strips around streams and lakes, and preserve
forested areas and wetlands.
Leave as much vegetation as possible when clearing
Install silt fences, stormwater detention and retention
ponds, and sediment basins to retain sediment on site.
Manage stormwater to minimize the adverse effects of new
Develop and implement a stormwater management program for
Require contractors and developers to consider solutions to
the long-term impact of runoff from the development.
Consider the impact on streams, rivers, and lakes when
making planning and zoning decisions.
Protect wetlands. Wetlands are proven to filter pollutants
before they enter other bodies of water.
Identify potential sources of NPS pollution, such as
eroding roadbanks. Take corrective action where needed.
Install good stormwater management practices in areas that
are already developed.
Businesses and Factories
Monitor wastewater for hazardous chemicals from the
Prevent leaks and spills of hazardous substances.
Follow government regulations pertaining to storage tanks.
Develop best management practices (BMPs) designed
specifically for that type of business.
Swimmers, Boaters, Anglers
Limit speed and obey boat speed limits. Boat wakes erode
riverbanks and lake shores, thereby releasing sediment.
Dispose of trash and toilet wastes properly, both on shore
and in the boat.
RIPARIAN ZONES MAINTAIN STREAM HEALTH
A riparian zone is the area of land immediately adjacent to
a stream. Typically the area is 35 or more feet wide on
either side of a stream and may experience frequent flooding.
Importance of Vegetation
Vegetation growing within a riparian zone is essential to
the maintenance of a healthy stream system. For example,
trees in the riparian zone shade the water resulting in lower
water temperatures in the hot summer. Cooler water has
greater oxygen carrying capability. Leaves from trees and
bushes provide raw organic material for the food chain. The
dense, deep root systems of the riparian plants help hold the
stream banks together during flooding. Riparian vegetation is
essential during floods for slowing the flow of water and
protecting adjacent land from the scouring effects of flood
A healthy stream depends on well-managed riparian zones.
Sparse vegetative cover causes flooding and water quality
problems. Maintaining and restoring natural riparian
vegetation can prevent many water quality problems.
A major function of stream banks is to contain flowing
water. Stream banks offer much more than flow control. They
are an intricate part of the health of the entire stream
Healthy, well-managed riparian areas have a variety of plant
species growing on each bank. These areas also have a layer
of dead leaves on the ground that contribute to the thick
water-holding humus layer in the soil and allow water to seep
into the groundwater table. A lack of stream bank erosion is
a good indicator of a well-managed riparian zone.
Poorly managed stream systems generally lack trees and
important vegetative cover along the riparian zone. If there
is some vegetation, it is usually sparse and occupies less
than 35 feet on either side. Parking lots, buildings, and
mowed lawns adjacent to the bank's edges are places where
urban riparian vegetation may have been destroyed.
Making a Difference
Maintain at least a 30-foot vegetative buffer between a
lawn and stream.
Plant native trees and bushes to help revegetate the
Practice good lawn care techniques to prevent excess runoff
Talk to and educate neighbors about taking care of streams
and riparian zones.
Wetlands Protect Water Quality
Wetlands are among the most diverse and productive natural
resources on Earth. There are two basic types of wetlands,
tidal and nontidal. Nontidal wetlands are not subjected to
the ebb and flow of tides. These include bogs, marshes,
swamps, and ponds. More than 75% of Virginia's one million
acres of wetlands are nontidal.
In order to qualify as a wetland, an area of land must:
Have water on or near the surface for all or part of the
Have soil identified as wet (hydric) soil.
Have living plants that occur in wet soil (hydrophytic
Benefits of Wetlands
Wetlands help regulate and maintain the hydrology of rivers,
lakes, and streams by storing and slowly releasing
floodwaters. They help maintain water quality by storing
nutrients, trapping and filtering out sediment and
pollutants, purifying surface and groundwater, providing a
natural means of flood control and storm damage protection,
and controlling soil erosion.
Wetlands are critical to fish and wildlife populations. They
provide an important habitat for about one-third of the plant
and animal species federally listed as threatened or
Human activities have changed and destroyed many wetlands.
Wetlands have been filled in to make way for development
projects; drained and cleared to create croplands; and
dredged and channeled for navigation. It is critical that
these destroyed wetlands be restored or replaced in order to
maintain a healthy ecosystem.
Making a Difference
Regulate activities that destroy wetlands.
Provide tax incentives for preservation.
Manage publicly owned wetlands properly.
Identify sensitive wetlands areas on the property.
Ensure that activities compatible with wetlands
preservation are carried out on the property.
Donate or sell sensitive lands or easements to government
agencies or private groups dedicated to wetlands
Make public officials aware of the need to protect
Support conservation initiatives by public and private
groups concerned with wetlands protection.
Monitor wetlands and become involved in the regulatory
Learn more about wetlands and their values.
Inform friends, neighbors, and coworkers about the
importance of protecting wetlands.
WATER QUALITY MONITORING
Data is needed to identify troubled streams and/or to spot
trends that will cause future problems. This will lead to the
initiation of corrective action. There are three approaches
to assess the health of a stream: a stream walk, biological
monitoring, and chemical monitoring.
Before deciding which type of monitoring to pursue, find out
what monitoring may already be in progress. Check with other
groups in the watershed (citizen groups, homeowner
associations, youth groups), the local Department of Health,
the local Department of Public Works, and state and federal
environmental agencies. Investigating a little time in the
beginning may prevent duplication of efforts later.
Conduct a Stream Walk
The U.S. Environmental Protection Agency (EPA) has
Stream Habitat Walk procedure where volunteers
periodically walk along a stream observing and recording its
physical condition. Visual observation of erosion or
impairment of vegetative habitats could result in immediate
The general health of a stream can be measured by comparing
the differences in insect populations and diversity of insect
species between impaired and unimpaired streams. Healthy
streams have diverse families of aquatic insects. Biological
monitoring procedures describe how to collect
macroinvertebrates (aquatic insects) in a systematic manner
and how to count the numbers of each different kind or
family. This examination will yield a measure of the degree
of pollution but not the type of pollution. The Northern
Virginia Soil and Water Conservation District provides
training, equipment and reporting forms.
Measuring the concentration of certain chemicals in a stream
will directly identify pollutants and often give an
indication of the source of the pollution. Water samples can
be analyzed, using easy to obtain kits, to determine
concentrations of key pollutants. The following parameters
may be measured: temperature (air and water), acidity (pH),
dissolved oxygen (DO), nitrates (N), phosphorus (P),
turbidity, suspended solids, and fecal coliform.
Do not go to stream alone.
Wear proper clothing.
Avoid flood stage and storm conditions.
Be able to identify poisonous plants and animals and avoid
Know the location of the nearest medical center.
Wash carefully before eating, rubbing eyes, or touching
mouth, after being in a stream. There may be poisonous
substances or biota in the water.
THE SEPTIC SYSTEM AND THE WATERSHED
Septic systems are individual household wastewater treatment
systems that use soil to treat small wastewater flows. Septic
systems are generally found in rural and large-lots settings
where centralized wastewater treatment is impractical.
Ground and surface water are integral components of a
watershed and either potentially can interact with the normal
functioning of a septic system. A properly functioning septic
system does not pollute the groundwater. On the other hand,
an improperly functioning system can cause a serious health
threat to family and neighbors, degrade nearby waterbodies
and groundwater, reduce property value, be costly to repair,
and put water supply users at risk.
Causes of Malfunctions
Improperly cleaned systems, clogged drainfield lines,
frequent use of chlorine bleaches, tree roots in the system,
a water table higher than the system, poor soil percolation,
and saturated soils all cause septic system failure and
possible water contamination.
A septic system treats wastewater by allowing solids to
settle in the tank and excess water to seep into the
subsurface soil which in turn filters the pollutants.
Problems occur when the soil becomes plugged with solids
carried from the septic tank to the drainfield. Once soil
becomes plugged, it is not able to absorb the water from the
septic system resulting in surface ponding of wastewater,
which can be carried by rain to neighboring streams. A
similar scenario occurs if tanks and drain lines are clogged
allowing wastewater to enter soil untreated.
Sewage surfacing over the drainfield, especially after
Sewage back-ups in the house
Lush, green growth over the drainfield
Slow draining toilets or drains
Make a Difference
Have the tank pumped out and system inspected every 3-5
years by a licensed septic contractor (listed in the yellow
Keep a record of pumping, inspections, and other
Practice water conservation. Repair dripping faucets and
leaking toilets, run washing machines and dishwashers only
when full, avoid long showers, and use water-saving
features on faucets, showerheads, and toilets.
Learn the location of the septic system and drainfield.
Keep a sketch of it handy for service visits. If the system
has a flow diversion valve, learn its location and turn it
once a year. Flow diverters can add years to the life of
Divert roof drains and surface water from driveways and
hillsides away from the septic system. Keep sump pump
outlets and house footing drains diverted as far away from
the septic system as possible.
Take leftover hazardous household chemicals to an approved
collection center for disposal. Use bleach,
disinfectants, and drain and toilet bowl cleaners sparingly
and in accordance with product labels. Look for those that
state septic system safe.
Leave the area covering the drainfield undisturbed with
only a mowed grass cover. Roots from nearby trees and
shrubs may clog and damage the drain lines.
Don't drive or park on top of any part of the system.
Don't make repairs to septic system without obtaining the
required health department permit. Use professional
licensed septic contractors when repairs are needed.
Don't plant trees and shrubs near the septic tank or field.
Don't use commercial septic tank additives. These products
usually do not help and may hurt a system in the long run.
Don't use toilets or drains as trash cans by dumping in
Don't poison septic system and ground water by pouring
harmful chemicals down the drain. They can kill the
beneficial bacteria that treat wastewater. Keep the
following materials out of the system:
nondegradables—grease, disposable diapers, and
poisons—gasoline, oil, paint, paint thinner,
pesticides, and antifreeze.
A Healthy Lawn Helps the Environment
Lawn care knowledge and responsible practices are keys to
maintaining a good lawn and a healthy environment in the
Work with nature, not against it. Healthy grass provides a
feeding ground for birds who find it rich with insects and
worms. Thick grass prevents soil erosion, filters
contaminants from rainwater, and absorbs many types of
airborne pollutants such as dust and soot. Grass is also a
highly efficient converter of carbon dioxide to oxygen, which
helps clean the air.
Make a Difference
composition tested. Virginia Cooperative Extension can
recommend the nutrients that need to be added to support
the intended use.
Develop healthy soil. To grow well, lawns need soil with
good texture, some key nutrients, and the right pH or
Water deeply, but not too often. It's best to water only
when the lawn really needs it.
Choose a grass type that thrives in a specific climate. The
right type of grass, one that suits specific needs and
likes the local weather, will always yield better results.
Mow high, often, and with sharp blades. Keeping the blades
taller will produce stronger, healthier grass with a better
root system and fewer pest problems.
Correct thatch build up. When thatch gets deeper than 1/2
inch, it prevents water and nutrients from penetrating to
the soil and grass roots. Reduce thatch by raking the lawn
or using a machine to break it up.
Aerate soil. Aeration helps water penetrate soil and allows
air to circulate around the roots of grass. For information
about buying or renting a soil aerator, call a local
nursery or rental company.
Recycle grass clippings. Leaving them on the lawn can
reduce fertilizer application up to 70%. Cool season grass
should be fertilized in the fall to promote a healthy root
Set realistic goals. Putting green perfection does not have
to be a goal.
MULCHING: AN ORGANIC WAY TO RECYCLE
Mulch is organic material such as wood chips, grass
clippings, leaves, or compost that is spread over the surface
of the soil. Mulch is an easy way to recycle yard wastes.
What Does Mulch Do?
Mulch conserves water, keeps down weeds, and regulates soil
temperature. It also protects the ground from erosion and
compaction caused by rain and foot traffic. Mulch provides
ideal conditions for earthworms and other soil organisms
necessary for healthy soil and plants. Mulch breaks down into
humus, which feeds the soil. A good mulch should be readily
available, easy to apply, and stay in place without much
Before applying mulch, weed area.
Spread mulch around plants as far as the distance of its
outermost branching (the drip line) or cover an entire
Spread mulch thickly if water is able to penetrate and if
it does not smother the roots of the plant being mulched.
Three inches of mulch is safe for any woody plant and up to
eight inches is acceptable for large trees.
Avoid using thick mulches on azaleas, rhododendrons, or
other shallow-rooted plants.
Look in the yard. Every yard has grass or leaves that can
be made into mulch.
Wood chips. Contact a local tree service, landscaper or
Purchase shredders and chippers at lawn and garden equipment
Rotary mower: Run across dry leaves to make fine-textured
mulch for annuals and smaller plants.
Small electric chipper: Use on woody stalks and branches up
to 1/4 inches thick to make fine-textured mulch.
Gas-powered shredders: A five to eight horsepower unit is
capable of processing materials up to three inches in
Large gas-powered shredders: This type of unit can handle
woody wastes up to six inches in diameter. The larger the
machine, the faster the mulch-making.
Annuals and perennials: Use mulch that breaks down in a
relatively short period of time, such as grass clippings
Trees and shrubs: An attractive thick layer of wood chips
requires little maintenance.
Grass clippings: Spread in thin layers over vegetable and
flower beds or mix with leaves and spread in a thick layer.
Keep clippings to less than one inch to prevent matting and
to allow water to penetrate the soil.
Leaves: Leaves from deciduous trees can be spread as mulch
in the fall. Evergreen leaves can be used, but take longer
to turn a dark color and decay.
Sawdust and other finely ground woody materials: Use on the
surface, but do not mix into the soil.
COMPOSTING: AN ALTERNATIVE TO DISPOSAL
What is Compost?
Compost, also called humus, is recycled organic matter. It
is a dark, crumbly, partially decomposed collection of plant
products. Compost is created by a biological process in which
numerous bacteria break down the plant material.
What is the Value of Compost?
Composting is a practical, convenient way to transform yard
wastes into a resource. It is a valuable tool for anyone with
a garden, lawn, trees, shrubs, or even planter boxes. By
using compost, organic materials are returned to the soil.
The process improves plant growth by breaking heavy clay
soils into a better texture, adding water and
nutrient-holding capacity to sandy soils, and adding
essential nutrients to any soil. Improving the soil is the
first step toward improving the health of plants, reducing
fertilizer use, cleaning the air, and preventing soil loss
What can be Composted?
Many types of organic materials can be used for compost.
Sod, grass clippings, leaves, hay, straw, weeds, manure,
chopped corncobs, corn stalks, sawdust, shredded newspaper,
wood ashes, hedge clippings, and plant refuse from the garden
are just a few possibilities for compost.
Use care when composting kitchen scraps. Compost only
vegetable scraps. Do NOT compost meat scraps, bones, fatty
foods (cheese, salad dressing, and cooking oil), or pet
feces. These items may attract dogs, rats, and other animals
and may develop an unpleasant odor during decomposition.
Instead, place these items in the regular garbage.
ORGANIZE AND AFFILIATE WITH OTHERS
Individuals can enhance their ability to promote water
quality by forming small groups to reinforce efforts to
identify actual or potential problems and to exert the
necessary pressure to initiate corrective action. Affiliating
with state or national organizations with experience in such
programs will increase the effectiveness of such groups.
Make a commitment. Recognize that it takes an investment of
time and energy over a period of years. Don't get started
unless there will be a follow through effort on the
Limit objectives. Select a portion of a waterway or stream
to place under continuing care.
Form a group. Publicize the effort. Contact local homeowner
organizations, conservation groups, civic associations, and
youth groups to provide support and a membership base. Have
a kickoff meeting.
Develop an action plan. Perform an initial "stream
walk" to inventory problems. Plan responses to obvious
problems. Get advice from established organizations when
making an action plan.
Know the law. There are many laws and ordinances designed
to protect the environment and regulate hazardous
activities. Call state and local officials for more
Establish an organizational structure. Define and assign
responsibilities. Survey the community for talent and
Obtain backing of local political organizations and of the
national/state volunteer organizations dedicated to
improving water quality. Contact the
Northern Virginia Soil and Water Conservation District as a
first step to networking with the involved organizations.
Do something concrete and rewarding. Plan and conduct a
stream cleanup. Involve the entire membership of the
Initiate water quality monitoring. Affiliate with an
organization such as the Northern Virginia Soil and
Water Conservation District or the
Audubon Naturalist Society and obtain training, kits,
and survey forms. Assign monitoring points to small groups
of volunteers to keep people active and to see hard
Publicize. Spread the news about findings and corrective
actions to be taken to improve water quality. Conduct
seminars for homeowners on lawn care, fertilizing,
mulching, and composting.