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A NEW SPIN ON WATER STUDIES
Drinking Water? Convincing Kids that it
Matters.
Margaret Busker-PostlethwaitBuchtel High School Akron, Ohio
Overview
Background – Distribution Systems and Drinking Water Quality
Review of Akron, OH Drinking Water
SystemStudent Activities-Demonstrations Resources
Background Information
Drinking water in cities mainly comes from a reservoir or aquifer.
Surface water-biological pollutantsGround water-possible leachates
What’s so special about this Unit?
• Most focus on watershed, which is important, but does NOT possess final characteristics of the water we drink
• Water Treatment Plant primary function – reduce organics in water, reduce turbidity, and add disinfectant at plant
• For drinking water, critical items-regulations are human health issues (heavy metals and disinfection byproducts) – how does the distribution system impact water quality?
• Students care about the water they actually drink
• Many “problems” (science and social) with drinking water to investigate and use to drive learning
Unfortunately there are very few experiments or demonstrations examining the relationship between drinking water quality and the distribution system. . . . . . . . . until now . . . . .
According to USGS:
In the United States, more than 250 million people depend on the fresh water in our rivers, lakes, streams, and groundwater supplies for their drinking water.
Water Sources
Water: From Reservoir to Tap
Watershed (Cuyahoga)
Reservoir (Lake Rockwell)
Treatment Plant (city of Akron)
Water Distribution System
Homes
Distribution Systems 101
1 2 3 4 5
0
0.5
1
1.5
2
Chlorine vs. DBP
There are general relationships between:
1. distance from water plant and water age
2. water age and chlorine residual3. water age and DBPsChlorine
residual measurement of tap water gives us a lot of information!
Akron City Water
Water comes from a reservoir called Lake Rockwell.
Lake Rockwell is fed by the Cuyahoga River which comes from Lake Erie.
The Cuyahoga River begins and ends in Lake Erie.
Akron’s Wastewater Treatment plant also uses the Cuyahoga River for it’s discharge.
Water supply schematic This is from the State’s EPA site. The information in the TMDL (total maximum daily load) reports can be very useful. In this schematic students can see that their drinking water reservoir also is linked to other community’s waste water systems further up stream. A good way to create discussion about our impact on other watersheds.
http://www.epa.ohio.gov/portals/35/tmdl/MidCuyFinalTMDL.pdf
Distribution System Basics
Distribution System consists of:• Pumps that deliver water from the water
plant to storage tanks in the city• Pipes that deliver water from storage
tanks to homes and businessesDistribution System provides:• Water to meet demands (quantity and
pressure) of homes and businesses• Water quality that meets Federal
regulationsBe careful – some cities use booster chlorination! Booster chlorination is addition of chlorine at another point in system (in addition to the water plant). It is not very common.
Drinking Water Quality 101
• Disinfect with chlorine (added at water plant) to prevent biological contamination-waterborne diseases
• Chlorine decays (i.e. goes away) in the distribution system
• Chlorine reacts with dissolved organic matter (from natural sources) to form disinfection byproducts (DBPs)
• DBPs are known carcinogens and regulated in the drinking water system
DBPs much, much lower if a groundwater source!
The Unit
Pre-assessmentGuskey Cycle (teach, re-teach, enrichment)CSR- Collaborative Strategic ReadingNotes on Water (reading road map)Guided readingWater testingAssessmentEnrichment
Unit Procedures:
Day Activity Teacher Student Notes
Day 1 Pre test Hand out test Take test Discuss
Day 1 Introduction
Students read “What is in Drinking water” and complete CSR
Introduce and lead
Read and complete CSR
Possibly have lower ability readers pair up with another student
Discussion Facilitate Share CSR’s
Vocabulary Watershed, pathogen, DBP’s, water quality, disinfection, treatment, ground water, surface water, pollutants
Write Vocabulary on board
Students copy vocab and define
Remind that vocab is a running challenge.
Explain protocols for bringing in water samples for next class
Sample must be fresh and in a “clean” container
Get water samples from home
Focus on WWTP’s going into lake Rockwell- thus need for disinfection?
Day 3-6 LABStudents are split into 3 stations
Station ONEGuided investigation of water quality reports / water tests
Print out quality reports with focus on DBP’s from disinfection, watershed maps, toxicology/fact sheets on DBP’s
Students read through packets and answer questions as a group
Questions are modeled afterBloom’s Taxonomy
Station TWOTest Water
Students bring up samples and we test in small groups.
Students continue to work on sheets and record their Cl data.
Station THREEWork station
Students may either work on their Testing results and lab or guided reading or vocabulary
Day 5 Revisit pre assessment
Facilitate In groups students discuss the pre ass.
Reflection and wrap up
Students complete the BIG WATER PICTURE
Students write
Chance to catch up with other students
Day 6 Wrap up and ASS. Facilitate Students share their group results from lab/investigation activity
Assessment Monitor Take assessment
Grade overnight
Day 7 Re-teach and enrichment
Re-teach: Activities from the bookEnrichment: Test school water and make a PSA for school?
Keys to success
Know your students- this was NOT the first lab I did- I got them excited about it in September and we did it later.
Do guided reading activities with them prior to this so that they know how to read and answer questions.
Be flexible Invite guest speakers in- I had
rangers from Akron Water Pollution Division, Akron’s Waste Water Treatment Plant, Enviroscience, and Soil and Water Conservation District.
Let them know how expensive and cool the test equipment is!
Give them a period of 2-3 days to bring in water samples (you can’t test them all in one class period anyway)
GUSKEY CYCLE Pre-test Teach Assess (80% is
mastery) Enrichment/re-teach Re-test
Activities
Testing group Testing their water
sample with instructor Plotting their results
on city map Drawing conclusions
about levels of chlorine vs. DBP’s and age of water
Answering conclusion questions
Reading group Reading water quality
reports Answering questions
which are based on Bloom’s taxonomy
Interpreting data
What it looks like
Students testing their water sample and completing their guided reading using the Akron Water Treatment Brochure .
sample work
Water Testing-Indy Style
Indianapolis receives its water from the Geist Reservoir which is fed from the Fall Creek.
Chlorine is added at the treatment plant and is not typically “boosted”
Activities
Testing group Testing their water
sample with instructor Plotting their results
on city map Drawing conclusions
about levels of chlorine vs. DBP’s and age of water
Answering conclusion questions
Reading group Reading water quality
reports Answering questions
which are based on Bloom’s taxonomy
Interpreting data
Indianapolis
The Geist Reservoir is the main source for Indianapolis
This information is available on line in almost every city through the local public works.
Water will be coming in from reservoir entering city from the north. Water is pumped throughout the grid system.
Indianapolis Drinking Water
The amount of chlorine (as sodium hypochlorite, or bleach) that is added at the plant will depend on many factors, including the flow through the plant and the temperature of the water. Citizens initially measures chlorine at the treatment plants, then again throughout the distribution system to ensure that sufficient chlorine remains in the water at the “ends” of the system. There are a couple of locations where additional chlorine can be added (again as bleach), but in general, we try to manage chlorine levels by ensuring that the water is used by customers.
Ann McIverCitizens Water Group
Indianapolis Documents
http://www.citizenswater.com/WaterQuality/TreatingDrinkingWater.aspx
Mapquest
Data Collection
Locate the water sample location on the map of the city.
Write your data on a “sticky” and place it on the location.
Data Analysis
Which samples had higher Chlorine levels?Which samples had lower Chlorine levels?What can we infer about DBP’s and Distance
from Water treatment plant?
Conclusions
Is chlorination harmful or helpful?What about ground water?Because chlorination is used kill bacteria,
what can we do in order to decrease the need for chlorination?
Other thoughts?Can this be used in any classroom?
Resources
HACH (www.Hach.com): ~$400 for pocket colorimeter (chlorine only) and ~$700 for Model DR/820 (20+ water quality measurements), and~$0.20
per sampleYour City website (look under Utilities)CCR (Consumer Confidence Reports) – all citieshave them, a standard report on water quality for regulated parametersGoogle Maps (City)OhioEPA (www.OhioEPA.gov)Public drinking water systems informationWatersheds-water quality