Freshwater Resources Natural Systems, Human Impact, and Conservation.

Freshwater ResourcesNatural Systems, Human Impact, and Conservation

Freshwater Systems•Fresh water – water that is relatively

pure, with few dissolved saltsAll water

2.5 % Fresh Water

97.5% Oceans

Fresh Water

1% Surface Fresh water

20 % Groundwater

79% Ice Caps & Glaciers

Surface Fresh Water

1% Water within organisms

1% Rivers

8% Atmospheric Water Vapor

38% Soil Moisture

52% Lakes

Uses of WaterAgricultural Domestic Industrial

Irrigation Bathing Washing

Water for Livestock Laundry Diluting

Consumption/Cooking

Cooling

Landscaping

Hydrologic Cycle

•Water is constantly moving among reservoirs.

•It redistributes heat, erodes mountain ranges, builds rivers deltas, maintains organisms & ecosystems, shapes civilizations.

Rivers & Streams wind through landscapes•Rain, snowmelt, springs run downhill &

converge forming streams, creeks, brooks merge into rivers

•Tributary – smaller river flowing into a larger one

•Watershed – Area of land drained by a river and all its tributaries.

Rivers

•Shape the landscape

•Erode Soil from the bank

•May shift from one course to another,

creating floodplains

•Hosts diverse ecological communities

Watershed

• Region of land that contributes water to a stream, river, pond, lake, or ocean

• Watershed Divide: Boundary that divides one watershed from another.

• Every land area is part of a watershed

• Depend on geology of region.

• Vegetation types of plants determine how much & how quickly water runs.

Watershed Characteristics

Runoff

•Keep rivers and lakes full of water, but also changes the landscape.

Meteorological factors Physical characteristics

Type of precipitation Land Use

Rainfall intensity Vegetation

Rainfall amount Soil Type

Rainfall duration Drainage Area

Distribution of rainfall over the watersheds

Elevation

Watersheds Change Over Time

•Land use changes must be monitored, urban, agricultural, industry, transportation systems, & public lands.

•Monitoring areas susceptible to flooding

Stream flow Measurements Indicate Change •Measure the amount of water (volume)

that flows past a certain point over time (velocity).

•Influenced by soil conditions, vegetative coverings , human population, wetlands, forests, urban settings.

Chicago Over Time…….

Mississippi Watershed

•40 % of 48 states (made of smaller watersheds)

Chicago River

• How Healthy is the Chicago River Watershed?

1. Diversity (plant & organisms)2. Any pollutants?3. Invasive Species?

What Makes A River Healthy?

•Flow

•Water Quality

•Habitat

•Food Energy

What are the problems facing the Chicago River Today?

•Loss of Biodiversity/habitat•Toxins in the water and sediment•Excess Nutrients•Excess fecal coliform bacteria•Excess Erosion•Presence of Dams•Lack of public awareness and action

Water Quality Testing

•Oxygen•pH•Temperature•Phosphates•Nitrates•Turbidity & Total Solids•Fecal Coliform•Aquatic Macroinvertebrates•Habitat

Today….•Reflection Sheet Due Turn it in!

•Finish Colorado River Case Study – pg. 388 (15 min)

•Watershed Movie: A New Ethic

How We Use Water

•Consumptive use – remove water from an aquifer or surface water body and do not return it.

•Nonconsumptive use – does not remove water, or temporarily removes water

Industry Agriculture Domestic

United States 46% 41% 13%

India 6% 87% 8%

Lithuania 16% 7% 78%

Dams & The Environment

•Any obstruction placed in a river or stream to block the flow of water so that water can be stored in a reservoir.

•Prevent floods, provide drinking water, facilitate irrigation, and generate electricity.

•More than 45,000 have been erected!

Major Benefits & Costs of DamsBenefits Costs

Power Generation Habitat alteration

Emission reduction Fisheries Decline

Crop Irrigation Population displacement

Drinking Water Sediment Capture

Flood Control Disruption of Flooding

Shipping Risk of Failure

New Recreational Opportunities

Lost Recreational Opportunities

Some dams are being removed

•Restore ecosystems, reestablish economically valuable fisheries, and revive river recreation.

•500 dams have been removed in the US

Dikes & Levees are meant to control floods

•Flooding is a natural process due to snowmelt or heavy rain, spread nutrient-rich sediments over large areas.

•Short term damage farms, homes, and other property

Canals

•Water from upstream reservoirs are routed downstream by the use of canals

•Hazardous to people and animals

•Lead to serious unanticipated environmental problems

Channelization & the Environment•Straightening, deepening, widening,

clearing, or lining existing stream channels.

•Control floods, improve drainage, control erosion, and improve navigation.

•Degradation of hydrologic qualities, removal of vegetation, downstream flooding, aesthetic degradation.

Wetlands include marshes, swamps, and bogs

•Enormously rich and productive

•Valuable as a habitat for wildlife

•Slow runoff, reduce flooding, recharge aquifers

Lakes and Ponds are ecologically diverse systems

•Bodies of standing water

•Vary with depth and distance from shore

Littoral Zone

•Edge of body of water, shallow

•Aquatic plants grow from the mud

•Rich in invertebrates, insect larvae, snails, crayfish

Benthic Zone

•Extends along the bottom of the entire water body

•Invertebrates live in the mud, feed on detritus or on one another

Limnetic Zone

•Open portion, away from shore

•Sunlight intensity decreases with depth

•Photosynthetic organisms thrive

Profundal Zone

•Sunlight Does not Reach

•Lower is dissolved oxygen, supports fewer animals

Groundwater

•Any precipitation that does not evaporate, flow into waterways, or get taken up by organisms.

•Aquifers: porous, spongelike formations of rock, sand or gravel that hold water.

2 Broad Categories • Confined Aquifer –

water bearing porous layer of rock, sand, or gravel that is trapped between layers

• Unconfined Aquifer – no upper layer, water is under less pressure and can be readily recharged by surface water

We are depleting groundwater

•Aquifers recharge slowly, groundwater becomes more difficult and expensive to extract.

•Lose water, become weaker and less capable of supporting land surface.

•Sinkholes grounds gives way with little warning.

Chicago Sinkhole 4/18/13

Fresh Water Pollution & Its Control

Pollution

•The release of matter or energy into the environment that causes undesirable impacts on the health and well-being of humans or other organisms.

Water Pollution Takes Many Forms•Nutrient Pollution

•Pathogens and Waterborne diseases

•Toxic Chemicals

•Sediment

•Thermal Pollution

Water Pollution

•Point Sources Discrete locations, factory or sewer pipe

•Non Point Source Multiple cumulative inputs over larger areas

Groundwater Pollution

•Serious Problem, more difficult to manage

•Less dissolved oxygen, microbes, minerals, and organic matter

•Many sources of pollution

Wastewater and Its Treatment

We treat our drinking water

•Mainstream practices due to advances in technology

•Regulated by the EPA

•Chemicals, passed through filters of sand, gravel, and charcoal, and or disinfected with chlorine.

Wastewater

•Water that has been used by people in some way

•Carrying water sewage, water from showers, sinks, washing machines, dishwashers, water used in manufacturing, stormwater runoff.

•Harm ecosystems, and pose threats to human health

Wastewater Treatment

•Involves steps

•Septic Systems: Water runs from the house to an underground tank, solids and oils separate from water

Primary Treatment

•Physical removal of contamination in settling tanks or clarifiers

•Removes 60% of suspended solids

Secondary Treatment

•Water is stirred and aerated so that aerobic bacteria degrade organic pollutants.

•90% of suspended solids may be removed