Water Quality Indicators Water Pollution EPA Environmental Protection

Water Quality Indicators & Water Pollution

EPA - Environmental Protection Agency Ø Government agency responsible for protecting human health and the environment Ø Helps enforce water quality standards

Potable Water that is considered safe to drink = drinking water Ø Not all water is considered "potable, " and we have to monitor the quality of our water to make sure it is safe for us to drink. Ø We use many tests to make sure our water is "potable" or safe to drink Ø

p. H test 3. p. H - measures how acidic or basic the water is Ø 7. 0 is neutral Ø l l l Ø less than 7= acidic higher than 7=basic pure water has a value of 7 on the p. H scale Acid rain major source of the problem

Temperature: average amount of heat in water Varies due to seasons or location (higher elevations have cooler water) Cold water is better because it holds more oxygen.

Turbidity- clearness of water Affected by sediment, excessive algae growth and storms. Cloudy water is bad. In surface bodies of water, high turbidity can lead to increased water temperatures and low dissolved oxygen, which are not good for the health of aquatic organisms.

Chlorine Ø Water can come from a variety of sources, such as lakes and wells, that can be contaminated with germs which can make people sick. Ø Germs can also contaminate water as it travels through miles of piping to get to a community. To prevent this, water companies add a disinfectant that kills germs. Ø The most commonly added disinfectants are chlorine and monochloramine.

Copper occurs in drinking water primarily due to its use in plumbing materials and the corrosion of copper pipes. As with lead, all water is corrosive toward copper to some degree, even water termed noncorrosive or water that is treated to make it less corrosive. Ø The maximum contaminate goal for drinking water for copper is 1. 3 ppm. (limit for safe drinking water)

Hardness Ø Hard water is water that contains dissolved substances called minerals. These minerals contain the elements calcium or magnesium. Hard water is not a health risk but is a nuisance because of mineral buildup on plumbing fixtures and poor soap and or detergent performance.

Phosphates/Nitrates Ø 4. Phosphates and nitrates- come from fertilizer and animal waste Ø Causes algal blooms which depletes the oxygen which kills the fish

Nitrates/ nitrites continued Ø The drinking water standard for nitrate-N is 10 ppm, or one hundredth of a gram in one liter of water. The nitrite-N standard is 1 ppm. These standards only regulate public water supplies, but the health risks are the same for private well owners.

Nitrates/ Nitrites Ø Nitrates are essential plant nutrients, but in excess amounts they can cause significant water quality problems. Ø Sources of nitrates include wastewater treatment plants, runoff from fertilized lawns and cropland, failing on-site septic systems, runoff from animal manure storage areas, and industrial discharges that contain corrosion inhibitors.

Bioindicators The presence, condition, and numbers of fish, insects (macroinvertebrates), algae, plants, and other aquatic life provide accurate info about the health of freshwater Ø macro= large / invertebrate= without a backbone l macroinvertibrates= organisms without a backbone that are large enough to be seen without microscope Ø Good water quality = lots of biodiversity Ø Poor water quality= little biodiversity Ø

Types of water pollution Ø Point Source l Ø Pollution flowing from a single and identifiable source such as a discharge pipe from a factory, roadway, or leaking undergroud storage tank Non-Point Source l Pollution collected by rain falling over a larger watershed which is then carried by runoff to a nearby lake or stream, or by infiltration into the groundwater

Point Source Pollution Ø Hazardous and toxic materials from manufacturing and industry discharged directly into water - usually through a pipe or a leaky underground tank l l l Ø oil and gasoline solvents toxins and poisons heavy metals (arsenic, lead, mercury, etc. ) Thermal pollution - heated water caused dissolved oxygen (DO) content in a body of water to decrease - can result in fish kills Point source pollution became addressed by the Clean Water Act of 1972

Non-Point Source Pollution Harder to figure out exactly where it's coming from Ø pollutants collected by rainwater falling over a large watershed and carried directly into a river, lake, or stream Ø Gas, oil, chemicals, detergents, and other pollutants collected off of driveways, roads, and city streets flow directly down drains and storm sewers into a nearby body of water untreated Ø

Non-Point Source Pollution (continued) Ø Modern Farming is a major source of non-point source pollution l l Pesticides (bug killers) and herbicides (weed killers) can wash into nearby lakes and rivers Crop fields, especially after harvest, can wash large amounts of dirt and sediment into nearby likes and rivers Animal waste and manure can be a source of nutrients and harmful bacteria Fertilizer can be a source of nutrients, such as nitrogen and phosphorus, entering nearby lakes and rivers leading to the serious problem of eutrophication (can make algae grow too much and water loses oxygen = death of fish)