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Water as Technology: Uses, Impacts, and Policy

Water as Technology: Uses, Impacts, and Policy. Technology and the Environment Christopher Weber 4/12/05. Goals. After this lecture, you should understand: The importance of water in our lives What water is used for in the US How water is made and disposed of

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Water as Technology: Uses, Impacts, and Policy

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  1. Water as Technology: Uses, Impacts, and Policy Technology and the Environment Christopher Weber 4/12/05

  2. Goals • After this lecture, you should understand: • The importance of water in our lives • What water is used for in the US • How water is made and disposed of • Some basic issues of water quantity and quality • The difficulty facing environmental policymakers regarding technology

  3. Water: What is it? • Liquid composed of Hydrogen and Oxygen • Essential for all life • Environment for aquatic plants and animals • The reason we’re here today Image from: http://folding.stanford.edu/education/water.htm

  4. The Water Cycle Taken from: http://www.yvw.com.au/newed/seniors/water_cycle.html

  5. Water: Where is it? • Question: What percentage of the world’s water is present in rivers and lakes? • Answer: ~0.27% ! • Where’s the rest of it?

  6. Water: Where is it? Taken from: http://ga.water.usgs.gov/edu/watercyclefreshstorage.html

  7. Water: What’s it good for? • Of all the water humans use, how much goes to homes? • To Industrial Use?

  8. Water uses in the US, 2000

  9. What’s in your cup? • Water Quantity vs. Water Quality • Public water supply generally comes from • Surface sources (rivers, some lakes) • Groundwater • Processed by Water Treatment Facilities Taken from:http://www.epa.gov/safewater/

  10. Typical Water Treatment Process Taken from: LA Drinking water plant website

  11. Down the sink. . . Taken From: http://www.city.toronto.on.ca/water/wastewater_treatment/process.htm

  12. Activity – Water Pricing • 3 contestants • Water from 3 different sources • Pour into bucket until you reach $1 worth of water

  13. Five Gallon Bucket

  14. High End Bottled Water

  15. Grocery Store “Bottled” Water

  16. Pittsburgh Public Supplied Water

  17. Answers to Water Exercise • Evian- 0.03 of 5 gal bucket • Grocery Store Water – 1/3 of 5 gal bucket • Pittsburgh Water – 62 5 gal buckets

  18. Cost of Water Globally? Pittsburgh has one of highest costs for commercial water use in the country in 2000 (74,844 gallons for annual household use.) http://www.provwater.com/worldclass.htm, RI

  19. Focus Issue: Washing Clothes and Laundry Detergents • Both a water quantity and quality issue • Affects everyone! • Quantity—Some washers more efficient than others • Quality—Just what’s in your laundry anyway? • Start with an exercise using water and electricity pricing—comparison of Life Cycle economics of two washing machines

  20. Normal Washing Machine

  21. Efficient Washing Machine

  22. Calculation of Actual Washer Prices • 3 components— • Initial Cost • Water Cost • Electricity Cost • Lifecycle costing spreadsheet

  23. Initial Costs • How much would you estimate each of these washers to cost upfront?

  24. Initial Costs • How much would you estimate each of these washers to cost upfront? • Normal Washer ~ $300 • Energy STAR front-loader ~ $900 • Energy STAR washer costs 3X more! • Other potential benefits of front-loader? • Sound! • See if we can justify just on water and electricity

  25. Estimating Discussion • How much water does each washer use per cycle?

  26. Estimating Discussion • How much water does each washer use per cycle? • Normal Washer • 37 gallons • EnergyStar Washer • 19 gallons

  27. Estimating Discussion • How much electricity does each washer use per cycle?

  28. Estimating Discussion • How much electricity does each washer use per cycle? • Normal Washer • 1.57 kWh per load • EnergyStar Washer • 0.65 kWh per load

  29. Life Cycle Costs (with some assumptions) • Assume: • Electricity ~ 5.5 cents/kWh • Water ~ 0.397 cents/gal • Life Cycle of each washer ~ 12 years • Realistic? • 2.5 loads per week

  30. Overall Life Cycle Costs

  31. Water Quality Issues—Case Study: Eutrophication Taken From: http://www.umanitoba.ca/institutes/fisheries/227_305.jpg http://en.wikipedia.org/wiki/Image:Caspian_Sea_from_orbit.jpg

  32. Brief History of Water Quality and Eutrophication in the U.S. • 1930’s-40’s—Industry starts mass producing chemicals such as DDT, PCB’s, TCE, etc. • 1950’s—Water pollution truly starts to become evident • 1962—Silent Spring by Rachel Carson published, immediate public outcry against toxic chemicals • 1964—Eutrophication becomes evident all over US from nutrient pollution • International Joint Commission formed • 1969—Cuyahoga River/Lake Erie catches fire from pollution in water • IJC Commission Report suggests reducing Phosphate content in detergents • 1972—Clean Water Act passed (over veto by Nixon) • Wastewater treatment becomes law • 1974—Safe Drinking Water Act Passed • 1983 and 1987—Chesapeake Bay Agreements on Nutrient reduction • Early 1990’s—many states pass phosphorus bans for detergents

  33. Eutrophication—What is it? • Nitrogen (N) and Phosphorus (P) added to lakes or rivers • Algae grow quickly on elevated nutrients • When algae die, decomposition depletes oxygen • Lower oxygen levels kill fish and aquatic life Image taken from: http://www.biologymad.com/Crops/Crops.htm

  34. Eutrophication—What Causes it? • Caused by elevated levels of N,P in water—usually due to humans • Many possible causes! • Municipal wastewater emissions • Industrial Emissions • Crop Agriculture (fertilizer runoff) • Animal Agriculture (animal wastes) • The “Big” problem: • N,P are naturally occurring and non-toxic • Hard to trace and hard to determine who’s to blame

  35. Eutrophication—What Causes it? Pennsylvania Watersheds • Terminology—Point source vs. Non-point source • Point source pollution occurs at one point • Wastewater effluent • Combined Sewer Overflow • Non-point occurs over entire watershed • Agricultural ‘runoff’ Image taken from:http://pa.water.usgs.gov/pamaps/pa_basins.gif

  36. Link to Laundry . . . • One of major suspected routes of P pollution was in detergents • Detergents had a lot of Phosphates in them (20-35%)! • Phosphates not well removed in wastewater treatment • Can comprise up to 40% of P in wastewater

  37. Laundry Detergent: what makes it work? • What does a laundry detergent need to do? • ‘Grab’ soil and other stains • Pull the stain into solution • Keep the stain in solution • Brighten colors • Make the clothes smell pretty • Quite the technology, really!

  38. What makes it not work so well? • Water hardness (Ca, Mg, Fe) • Detergents require a ‘builder’ to stop this interference • Sodium Tripolyphosphate (STPP) works very well for this • Nontoxic, extremely effective ‘builder’ • Until 1960’s, the only builder used

  39. What’s a policy maker to do? • Exercise: it’s 1969, people want something done to ‘save’ Great Lakes, Chesapeake • You know: • Need to reduce P inputs to Lakes • Some Phosphorus due to point sources, some to agriculture • Detergents make up large portion of P in wastewater • Wastewater removal methods available

  40. What could be done? • The options: • Remove Phosphates from Detergents • Remove Phosphates from Wastewater • Work on Agricultural inputs • Any combination of the above • Several Questions: • Which is easiest? • Which is safest? • Which is cheapest? • Which would be most effective?

  41. Where it gets a little complicated… • Easy ≠ Cheap ≠ Effective ≠ Safe • Which is most important for an environmental policy? • Who should decide? • Who should pay? • The public? • The government? (another facet of the public) • Industry? (P+G, Colgate-Palmolive, etc)

  42. Option 1: Cut P levels in Detergents Example Environmentally-Friendly Detergent • Advantages (from gov’s perspective): • Easy—1 piece policy • Significantly reduce P load to wastewater plants • Financial burden goes to industry • Disadvantages: • Only part of part of P load • Industry backlash? • Still need detergent—what would replace it? Taken from: http://www.animalaid.org.uk/shop/household.htm

  43. Option 1: Cut P levels in Detergents Example Environmentally-Friendly Detergent today • Potential replacements all had problems— • Citrate was safe, but not all that effective • NTA arguably safe and effective, but questions about toxicity • Zeolite A safe and somewhat effective, but expensive • Industries already invested in NTA production • Precautionary principle? Taken from: http://www.animalaid.org.uk/shop/household.htm

  44. Option 2: Remove P from Wastewater • Advantages: • Target all point source P • Even then, fairly effective (much more so now) • Can keep Phosphates in detergents • Definite reduction after implementation • Disadvantages: • Very expensive—have to retrofit several hundred plants • Cost goes to municipalities • Still only deal with part of P load (point source) Precipitation unit for P removal Taken from: http://www.sewage-plants.de/en/technik/tertiaer/tertiaer.php

  45. Option 3: Work on Non-Point sources Fertilizer runoff into a river • Advantages: • In most watersheds, non-point are majority of load • Best practices can be low cost • Disadvantages: • Ignorance • Where it’s coming from? • Who and what is needed to fix? • Difficult to implement—need cooperation from many parties • ‘Soft’ solution—impacts not definite Taken from: http://www.concordma.com/magazine/sepoct01/scummyseptriver.jpeg

  46. Tradeoffs • Detergent substitution easy, cheap, and arguably effective • But might be unsafe • Wastewater Removal easy, effective, and safe • But expensive for municipalities • Non-point Sources safe and cheap and could be effective • But certainly not easy, and might not do anything

  47. Long Story Short • US focused on detergent substition initially • Took 10 to 20 years to find a suitable blend of substitutes • Some work was done on P removal in wastewater • In 1980’s, became evident that solution was not working • Some highly improved waters, some not • More focus as of late on agricultural practices • Eutrophication remains problematic in many areas of the country • Even worse now with growth of factory farming

  48. Summary • Policy makers must account for several things in making decisions about technology • Public Safety • Environmental Safety • Economic efficiency (for who?) • Water quality issues can be difficult problems to fix!

  49. Questions?

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