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Water and Watersheds. Maia McGuire, PhD Marine Extension Agent. Water…it’s all around us. 97% of the water on earth is SALT WATER 2% of the water on earth is GLACIAL ICE 1% of the water on earth is FRESH WATER that can be utilized. The Water Cycle. Vapor transport. Precipitation.
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Water and Watersheds Maia McGuire, PhD Marine Extension Agent
Water…it’s all around us • 97% of the water on earth is SALT WATER • 2% of the water on earth is GLACIAL ICE • 1% of the water on earth is FRESH WATER that can be utilized
The Water Cycle Vapor transport Precipitation Evaporation Transpiration Surface runoff Percolation Groundwater flow
Florida’s water cycle • 150 billion gallons per day = rainfall • 26 billion gpd = surface water and groundwater inflow • Evapotranspiration = 107 billion gpd • 66 billion gpd = surface water and groundwater outflow to oceans • 2.7 billion gpd = consumptive use
Watershed • The area of land that drains into a particular water body • Water can drain through natural (streams, rivers, porous rocks) and human-made waterways (canals, ditches) • As water flows, it picks up and carries particulate and dissolved materials
Where does the water go? • Aquifers (underground lakes) • Florida’s primary source of fresh water • St. Johns River • Intracoastal waterway • Atlantic Ocean • Lakes, ponds, springs
Water pollution • Point-source pollution • Source is known • Relatively easy to monitor and control • Non point-source pollution • Runoff/stormwater • Specific source not known • Difficult to regulate
Controlling non point-source pollution • Designed to hold the first 1” of rainfall runoff • Biological or physical removal of contaminants • Stormwater retention/detention ponds
Use semi-porous paving materials • As impervious surface increases, runoff increases and infiltration decreases
Common pollutants • Nutrients • Petroleum products • Sediment • Chemicals & metals • Thermal pollution
Nutrients (= fertilizer) • Nitrogen • Phosphorus
Nutrient limitation • When the LIMITING NUTRIENT is added, it prompts rapid algal growth (BLOOM)
Eutrophication • At night, algal bloom uses up oxygen rapidly • As algae die, they are decomposed by bacteria which also use up oxygen • Low oxygen conditions can kill shellfish, fish, etc.
Sewage • Boaters dump toilet waste illegally • Septic tanks fail • Sewer pipes break • Animal wastes from land are washed into the water
Oil pollution • 51% of oil entering the oceans comes from runoff • 5% is from big spills • 19% is from routine maintenance • 2% is from offshore drilling • 13% is from burning fuels (e.g. car exhaust) • 10% is from natural seeps
Did you know…? • On average, ½ cup of gas is spilled into the water every time a boat is fueled • 2 cups of gas spilled on a lake will contaminate over 1,000,000 gallons of water • 2-stroke engines discharge up to 25% of the fuel into the water unburned Source: Maine DEP
Sedimentation • Reduces ability of light to penetrate • Smothers benthic (bottom-dwelling) plants and animals • Often an indication that harmful things may be in the water (e.g. metals)
Thermal pollution • Power plant effluent • Paper mill effluent
“Water Quality” What we measure What affects the measurement Water Temperature Salinity Dissolved oxygen Nutrient concentrations Clarity (Turbidity) pH Chlorophyll a concentration Air Temperature, rain Rainfall, tide state Temperature, light, wind… Runoff, time of day, excretion Wind, runoff, boats Atmospheric conditions Nutrients, light
Drought/excessive water use • Reduces recharge of surface and groundwater • Increased salinity in estuaries and rivers • Saltwater intrusion into aquifers
What can we do? • Reduce water consumption • In the house • Short showers vs. baths • Toilets • Dishwashers, washing machines • Brushing teeth, washing hands • Repair leaks/drips/running toilets • Use cold shower/tap water to water plants
Restrict sprinkler usage (time of day and amount) • Use mulch • Use native, drought-tolerant plants • Reduce water consumption • Outdoors • Live with a brown lawn • Don’t wash car/pets on driveway • Cover your swimming pool
Protect the watershed • Reduce pollution • Follow directions when using chemicals • Fertilizers • Pesticides • Household chemicals • Automotive products • Dispose of containers properly • Use non-chemical (biodegradable) products • Pick up pet wastes
Boaters, please… • Use Pumpouts • Contain your garbage • Fuel responsibly • Use oil absorbing pads in your bilge
Prevent the spread of exotics • Non-native species are easily transported in bilge water or on boat motors. • Empty your bilges before transporting your boat • Remove plant material from your prop and discard in the garbage
Recycle… • Curbside recycling programs • Fishing line • Automotive/boat engine products • Mercury-containing devices • Office paper • Re-use containers when possible
Volunteer opportunities • Coastal Cleanups—3rd Sat in Sept • St. Johns River Cleanup—Mid-March • Monofilament recycling program • Nassau, Duval, St. Johns, Flagler • Clay • Putnam • Volusia www.fishinglinerecycling.com