Water Quality Is it safe and healthy?

● Certain substances can affect the taste or color of water, but are harmless unless present at very high levels. Other substances, such as certain chemicals and microorganisms can be harmful to your health.

pH ● What is it? –The measure of how acidic or basic a substance is ● Effects & Importance –Affects metabolism, growth, and development of many aquatic organisms –Can kill or harm fish if outside of the healthy pH range of 6.5 to 8.0 –Affected by: erosion, acid rain, human pollution

pH Mini Lab We will now complete a pH Mini Lab. You will need the following pH scale to help you.

Hardness ● What is it? –The combined level of calcium and magnesium –WHAT ARE THE SYMBOLS FOR CALCIUM AND MAGNESIUM ● Effects & Importance –Hard water does not form suds for cleaning, deposits and clogs pipes –NC has relatively “soft” water, about ppm –Directly affects pH and can cause stress for fish

Temperature ● What is it? –Cooler water maintains the proper nutrients and holds more dissolved oxygen than warm water. ● Effects & Importance –Changes affect the rate of photosynthesis and respiration. –Influences the sensitivity of organisms to toxic waste, parasites, and diseases. –Water has a high specific heat which makes it resistant to changes in temperature compared to most things

Dissolved Oxygen ● What is it? –Measure of free oxygen dissolved in water. ● Effects & Importance –Essential for healthy water systems. –Aquatic organisms need oxygen to survive. –Oxygen in the water is dissolved directly from the atmosphere or from photosynthesis –A healthy dissolved oxygen reading would be around 7 ppm or more

Turbidity ● What is it? –A measure of the clarity or clearness of water. ● Effects & Importance –Turbid water has lots of sediment, particles, and algae –Too much sediment is unhealthy and can smother plants and animals –Secchi Disk determines turbidity

● Nephelometric ● Turbidity ● Units ● Most rivers are around 10 NTU (except after rain or other event) 5 NTU 50 NTU 500 NTU

What element do you think has the following effects on water sources? Explain your thoughts to your neighbor.

Nitrates & Phosphates ● What is it? –Nutrients used for growth by plants and algae –Come from fertilizer, detergent, and mining runoff ● Effects & Importance –Small amounts of nitrates are needed in the water systems –Too much nitrate increases the amount of algae –Trees naturally filter nitrates

Bio Indicators ● What is it? –Living organisms used to assess the health of a water resource –Need specific conditions to survive ● Effects & Importance –When we see a bio indicator thriving, we can make conclusions about the health of the water –Can be positive or negative bio indicators