|
Brodhead Watershed
Drinking Water Threats
Whether your drinking water system depends on a "ground water source" (well) or a
"surface water source" (streams, rivers, lakes, springs, reservoirs, etc.), it
faces many threats to the quality and quantity of water it can supply.
Threats are those conditions which would affect people's health, if the water is
used for drinking, cooking and general hygiene purposes and could be either a
quality issue or quantity issue.
In many cases the quality of the drinking water source may make the water
unappealing (taste and odor concerns), but does not pose a health threat if
consumed, so it is not considered a threat.
Threats to your drinking water system may be either "man made" or naturally
occurring. Threats to our drinking water sources in the Brodhead Watershed can be
considered as
Groundwater Threats or Surface Water
Threats, although since the two are inseparably linked, a problem with one will
inevitably mean a problem with the other.
Groundwater Threats
Man Made Threats
Many human activities can negatively affect groundwater quality as well as
quantity. For many years it was generally believed that the filtering capabilities
of the soil protected groundwater from contamination by human activities on the
surface.
But with the discovery in the 1970's of human-made organic chemicals in
groundwater, we began to realize how extensively our activities can affect
groundwater. In fact, in a nationwide study commissioned by the U.S. Environmental
Protection Agency, 65% of the private wells tested failed to meet at least one
drinking water standard.
Those activities that can have a negative impact on groundwater can be categorized
in four groups: waste disposal, resource extraction, agricultural practices, and
urbanization.
Waste Disposal
The best known source of groundwater contamination is waste disposal sites
(landfills), both municipal and industrial, that were in existence before new
regulations went into effect in 1988.
Septic systems are another potential source of groundwater contamination. If
septic systems are improperly installed or maintained, bacteria, viruses, nitrate,
phosphorus, chlorides, and the organic solvents that are found in many household
cleaners as well as products sold to "clean" septic systems can all make their way
into groundwater. As a result of poor construction or maintenance of their septic
systems, rural homeowners are frequently the cause of contamination of their own
wells.
Resource Extraction
As mines intersect aquifers and collect water, they interfere with groundwater
storage and can lead to lowered water levels in wells.
Drainage from mining degrades water quality as it infiltrates aquifers or
discharges into streams. Increased concentrations of iron, manganese, sulfate, and
dissolved solids in well water can result. In the Brodhead Watershed, stone
quarries can have a negative impact on both groundwater and surface water sources.
Agriculture
Common agricultural practices such as fertilizing and applying pesticides are
coming under increased scrutiny because groundwater samples have revealed nitrates
and, in some cases, pesticides. The most prevalent problem is high levels of
nitrate from overapplication of manure and fertilizer. Nitrate is especially
harmful to babies, interfering with the blood's ability to transport oxygen, which
causes the baby to suffocate ("blue baby" disease).
Urbanization
Many human activities and land use practices, which proliferate with urbanization,
can negatively affect groundwater. Even cemeteries, for example, can contaminate
groundwater.
One effect of urbanization is recharge diversion. Soils that have been covered
with impervious surfaces-roofs, parking lots, or streets-obviously cannot absorb
precipitation. Nor can soils that have been compacted by heavy machinery. As a
result, much of the water from rain and snowmelt goes directly into streams and is
never available to recharge groundwater.
Large concentrations of people can also lead to overpumping of aquifers. This can
result in significant aquifer drawdown, which in turn reduces the quantity of
streamflow. Stream water quality then suffers due to higher concentrations of
sewage treatment plant effluent. Intensive pumping in coastal areas can cause salt
water to be drawn into aquifers and wells. Polluted stream water can also be drawn
into drinking water wells.
With increased population comes industrialization and an increase in the amount and
variety of industrial activities, many of which can potentially contaminate
groundwater. Leaking storage tanks at both industrial sites and gas stations have
contaminated groundwater in many instances.
Individual homeowners also impact groundwater through a number of activities.
These include improper disposal of used oil and overapplication of fertilizer and
pesticides on lawns and gardens. Homeowners use four to eight times the amount of
fertilizer and pesticides per acre than farms. Golf courses are another potential
source of groundwater contamination from overuse of fertilizer and pesticides.
Natural Contamination
The natural constituents of water that may affect its suitability for drinking and
other purposes most commonly found in groundwater are dissolved solids, calcium
carbonate, and iron. Concentrations of chlorides and nitrates can also restrict
use of water. These constituents enter water by leaching from rocks as water moves
through them. Hardness is a property of water, usually measured by the
concentration of calcium carbonate, which increases the amount of soap needed to
produce lather.
Radon, a naturally occurring radioactive gas formed from decaying uranium or radium
deposits, is a natural contaminant of increasing concern. Where radon is present
in bedrock it can dissolve in groundwater and become a health hazard either when
consumed or when the gas escapes into the air during showering, cooking, and
laundering.
Hydrogen sulfide is an infrequent natural contaminant of groundwater caused by
water storage in certain types of shale rock. It imparts a characteristic rotten
egg odor to the water, but is not seen as a health threat at the levels at which it
makes water unpalatable.
Corrosive groundwater is common. Corrosivity involves many factors including high
acidity and low concentrations of calcium carbonate. In a recent Penn State survey
of groundwater in private wells, 60% had corrosive water. Corrosive water
dissolves lead and copper from pipes and plumbing fixtures thus causing a health
risk.
Surface Water Threats
Because surface water (rivers, streams, ponds, lakes, reservoirs and springs) are
by their nature more "visible," most people have more experience with this water
source. Surface waters are often areas of recreation providing us with
opportunities for swimming, boating, fishing, and camping. Most of us have
pleasant memories and experiences related to these water habitats and view them as
a wonder of nature, representing crisp, clear, clean water.
However, surface waters are even more at risk of contamination than groundwater,
especially in the Pocono Mountain area where the Brodhead Watershed area is
located. This is due to the fact that this area is both a recreational area and a
high growth area. This increases the human activity within the watershed and,
thus, increases the chances of pollution.
While many of the threats talked about in the Groundwater
Threats section relate to surface water sources, surface water because of its
readily available nature is even more vulnerable to contamination. Surface waters
can be contaminated by pollution from "non-point sources"
sometimes called "polluted run-off" or "point sources" -
usually
permitted discharges from sewage treatment or industrial waste treatment plants.
Non-Point Source Pollution
Non-point source pollution threats are those threats to surface water sources that
cannot be traced to one particular discharge location. Run-off from farms, golf
courses, street and highway systems, parking lots, recreational fields, leaking
storage tanks or septic systems, railroad or vehicle accidents (i.e., chemical and
fuel spills), are all considered "non-point source pollution."
Combined, these potential sources of pollution in the Brodhead watershed area pose
the greatest threat to the water quality. These threats run the full course of
human activity from industrial and manufacturing centers, to the tourist industry,
agriculture, residential homes and recreational uses.
Nutrients and pesticides from golf courses, agricultural uses and residential homes
threaten the receiving waters. Chemicals and waste products from industrial and
commercial facilities, if not properly treated and disposed of, threaten surface
waters; air pollution from automobiles and combustion can find its way into the
hydrologic cycle; auto and truck accidents can introduce chemicals or fuels into a
water source, and run-off from parking lots and streets contains oil and grease,
nutrients, sediment and road chemicals.
A contaminated aquifer can influence a surface water source when it discharges into
a surface water source (e.g. when groundwater, contaminated by malfunctioning
septic systems or overuse of fertilizers or pesticides enters a stream).
Areas with high potential for causing non-point source pollution
Point Source Pollution
Point source pollution occurs at a specific point in the watershed. Generally
point source discharges are regulated by permits issued by the Department of
Environmental Protection. Most often these are permits for industrial waste,
sewerage wastewater or a stormwater discharge. The permitting process attempts to
minimize the impact of human activity on the surface water sources.
In the Brodhead Watershed there are numerous discharge permits and discharge
points, ranging from systems discharging 1,000 gallons per day up to 2.25
million gallons per day in size. While point source sites do not contribute the
volume of discharge to surface water sources that non-point source sites do, they
must be maintained and operated properly or they can have an immediate negative
impact on the receiving water body.
Point source discharges in the
Brodhead watershed
|