Lesson & Webquest

WATER QUALITY & TREATMENT

Mrs. McAven8th Grade ScienceRiverwood Middle School

MONDAY: WATER TREATMENT

• Now you’re on your own.

• Monday: See how a water treatment plant works: http://www.epa.gov/ogwdw/watertreatmentplant/flash/index.html

• Visit the site (http://www.epa.gov/safewater/watertreatmentplant/flash/) and complete your worksheet.

Let’s Start with some videos as a class.

Purifying Human WasteWater Recycling Plan

TUESDAY: WHY WE NEED TO CLEAN OUR WATER:

Let’s Start with some videos and a quick activity as a class.

Water Supply: https://www.brainpop.com/science/earthsystem/watersupply/preview.weml

Water Pollution: https://www.brainpop.com/science/ourfragileenvironment/waterpollution/preview.weml

Let’s discuss….What is the biggest problem with water quality? What factors affect water quality?

Would you be willing to drink the water if it was rust colored or had a funny smell? What substances can be found in water? Are all substances found in water harmful? Explain How do you think scientists determine the health of a body of water? What types of data would you analyze to predict the health of our water systems?

TUESDAY: WHY WE NEED TO CLEAN OUR WATER:

Choose one for each activity. Which water would you be willing to…

- take a bath in? - drink? - cook with? - brush your teeth with?

You may only choose each bottle once.

1 2 3 4

Water Sample # Observation 1 Very Clean River

2 Semi-clean Lake (some bacteria & silt)3 City (what comes out of your faucet)4 Bottle water containing deadly bacteria

TUESDAY: WHY WE NEED TO CLEAN OUR WATER:

Choose one for each activity. Which water would you be willing to… - take a bath in? - drink? - cook with? - brush your teeth with?

1 2 3 4

TUESDAY: WHY WE NEED TO CLEAN OUR WATER:

• Now you’re on your own.

• Follow through the reading and activities in this powerpoint and fill in your corresponding worksheet.

DON’T FORGET ABOUT… MONITORING THE HYDROSPHERE!

Remote Sensing: the scanning of the earth by satellite or high-flying aircraft in order to obtain information about it. Works best over LARGE areas.

Ground Truthing: is when a person visits a site and gathers data to draw a map of the site. Works best over small areas.

WATER IS ESSENTIAL TO LIFE….

• Water quality determines the health of ecosystems, human activity and human existence. It supports the human, animal, plant, and ALL living organisms functions. Without water the world would be a dry desert land with NO life.

It creates the weather that makes life possible. The oceans are a huge store of energy that regulates the temperature of the planet and keeps it at a level that allows us to live on the planet. It also allows for things like rain to fall giving us a source of fresh water. Without rain all of the water would eventually end up in the oceans and be too salty to support life.

WHAT ARE THE DIFFERENT TERMS TO DESCRIBE WATER QUALITY?

• An array of chemical, physical, and biological measurements is used to define water quality:

Potable water = water that is safe to drink (drinking water)

Safe water = can be used for cleaning and bathing (NOT drinking)

*The terms can be confusing. Be careful!

HOW DO WE MONITOR WHAT IS POTABLE WATER AND WHAT IS SAFE WATER?

U.S. ENVIRONMENTAL PROTECTION AGENCY• An independent federal agency established to coordinate

programs aimed at reducing pollution and protecting the environment

• Sets maximum levels for the 90 most commonly occurring water contaminants.

• Outlines the goals for a body of water by identifying its uses, protecting those uses, and establishing provisions to protect and preserve the water bodies for long term.

What is water pollution?

Read the full article here to get an understanding for water pollution: http://www.waterencyclopedia.com/Po-Re/Pollution-Sources-Point-and-Nonpoint.html

Point source pollution &

Non-point source pollution

The following slides and these websites will help you fill in your t-chart.Read through each section carefully.

#1 site: http://www.waterencyclopedia.com/Po-Re/Pollution-Sources-Point-and-Nonpoint.html

#2 site: http://oceanservice.noaa.gov/education/kits/pollution/02history.html

#3 site: http://water.epa.gov/polwaste/nps/outreach/point1.cfm

Water pollution is any contamination of water with chemicals or other foreign substances that are detrimental to human, plant, or animal health. Worldwide, nearly 2 billion people drink contaminated water that could be harmful to their health.

Point sources pollution- a specific source of pollution that can be identified.

Example: An industrial company spewing sewage into a nearby stream through a single pipe.

Non-point sources pollution- a widely spread source of pollution that can’t be tied to a specific point of origin.

Example: Acid rain entering the water cycle from pollutants being released from smokestacks. It enters the cycle and is harmful to fish and other creatures in fresh water lakes and streams.

VIDEO BREAK…LET’S THINK

Why care about water?:http://video.nationalgeographic.com/video/env-freshwater-whycare

DIFFERENT TYPES OF POLLUTANTSTo what degree does development and urbanization affect water sources for humans and wildlife?

Use the following slides and this website to explore the different types of pollutants.

Protecting Water: http://www.protectingwater.com/index.html

DIFFERENT TYPES OF POLLUTANTS• Pesticides: chemicals that are used to kill insects and other organisms.

These chemicals are washed off of plants (chemical run off) when it rains and are soaked up in the ground soil or flushed in a nearby water source. The chemicals tend to build up in human and animals bodies causing long term health problems. (Arsenic and DDT)

• Human waste: human activities cause most water pollution. 150 years ago, human waste was dumped into drinking water causing diseases like cholera to spread and kill. Dumping of human waste, such as septic tank leakage, and illegal dumping are still issues today.

• Industrial waste- is the waste produced by industrial activity which includes any material that is rendered useless during a manufacturing process such as that of factories, mills and mines. It has existed since the outset of the industrial revolution. Sewage treatment can be used to clean water tainted with industrial waste.

• Industrial waste examples: paints, paper products, industrial by-products, metals, radioactive wastes

• Chemical waste- factory processes involve toxic chemicals and strong acids. Toxic waste is released as a result of manufacturing. Laws try and control point sources of many chemical pollutions, however some factories still illegally release these chemicals.

• Stored chemical wastes in barrels cause nonpoint sources of pollution. These barrels tend to leak and can affect wildlife and water sources from afar.

• Smoke and exhaust : The burning of coal or other harmful materials from factories and car engines are another nonpoint source of water pollution. When coal, oil, and gasoline are burned they are released into the atmosphere as nitrogen and sulfur. This is pollution entering the water cycle as acid rain.

• Acid rain: when rain or any other form of precipitation is highly acidic, causing damage to human and wildlife.

WATER TREATMENT PROCESSESREASONS & REVIEW

WHY DO WE NEED TO TREAT OUR DRINKING WATER?

• Industrial runoff

• Agricultural runoff

• Road runoff

• Residential runoff

INDUSTRIAL RUNOFF

• Some industrial facilities generate ordinary domestic sewage that can run off into sewage drains.

• Industries that generate wastewater with high concentrations of conventional pollutants (e.g. oil and grease), toxic pollutants (e.g. heavy metals, volatile organic compounds) or other nonconventional pollutants such as ammonia, need specialized treatment systems.

AGRICULTURAL RUNOFF

• Nutrients (nitrogen and phosphorus) are typically applied to farmland as commercial fertilizer; animal manure; or spraying of municipal or industrial wastewater (effluent) or sludge.

• Nitrates and phosphates derived from these can pose health risks to humans if they end up in the drinking water.

• Sediment (loose soil) washed off fields is the largest source of agricultural pollution in the United States

ROAD RUNOFF• Sediments from construction sites and discharge of toxic

chemicals such as motor fuels and concrete washout into the storm drains.

RESIDENTIAL/URBAN RUNOFF

• surface runoff of rainwater created by urbanization.

• This runoff is a major source of urban flooding and water pollution in urban communities worldwide.

WATER TREATMENT PROCESS

http://www.youtube.com/watch?v=9z14l51ISwg&list=PL44OxmUx6A8pCBZRvLEg_fLf7WlWvwKod&index=2

STEP 1: RAW WATER INTAKE AND SCREENS• Intake structure - delivers water to the water treatment plant

• Lake or Reservoir

• Stream or River

• Groundwater

• Screens – prevent trash, logs, or fish from entering the treatment plant

STEP 2: COAGULATION AND FLOCCULATION• In coagulation, coagulants like lime and alum are

added to the water, which causes particulates to clump together.

• Next, the water is shaken into larger clumps, called flocs.

COAGULATION AND FLOCCULATION

STEP 3: SEDIMENTATION

• The sedimentation process requires that the water stand for 24 hours, which allows the clumps to settle to the bottom.

SETTLING BASIN

STEP 4: SECOND FILTRATION

The water is then filtered, disinfected (usually with chlorine) and aerated.Aeration helps to remove certain contaminants like radon.

5: DISINFECTION

• Disinfection – process designed to kill or deactivate most microorganisms in water, including disease causing bacteria

• Types of disinfection:• Physical

• Ultraviolet (UV) rays

• Heat

• Chemical• Chlorine

• Ozone

Giardia lamblia

Fecal Coliforms

6: STORAGE AND DISTRIBUTION

Storage – keeping water for later useElevated tanksGround storage tanks

Distribution system – network of pipes and pump stations that transports finished water from the treatment plant to the user

REVIEW TIMEStep 1: Watch - Fit to Drink

Step 2: Complete Thirsten’s Questions - http://www.epa.gov/safewater/kids/flash/flash_qagame.html

Step 3: Complete Thirsten’s Matching - http://www.epa.gov/safewater/kids/flash/flash_matching.html

What can you do? Fun links:http://environment.nationalgeographic.com/environment/freshwater/freshwater-resources/

EXTRAS• http://www.wonderville.ca/asset/water-treatment

• http://kidsenvirohealth.nlm.nih.gov/generic/2/games