1. Understanding Wastewater & Sewers
Erie County Department of
Environment & Planning
Division of Sewerage Management

2. Water
Is our Most
VALUABLE
RESOURCE
Most
Valuable

3. Why is Water IMPORTANT ? Water is necessary to all living things
People can live for weeks without food, but only a few days without water
Water is a delivery system
Nutrients in soil
Blood in humans/animals
Carries off bodily wastes
Our body is water cooled

4. Why Conserve Water ?
We have a limited
amount of water and
a growing population!

5. Who Uses Water ? People Industry Farmers
Supply
Who Uses Water ?
People
Industry
Farmers
Utilities (making electricity)
Water used in 1 day in USA billion gallons
450,000,000,000 gallons ( >7 trillion cups )

6. How Much Water Do We Use and Where ?

7. Water Trivia: US needs 115,000,000,000 gals/day of drinking water
Daily Water Usage
Family & Industrial US
Japan
Ghana (W. Africa)
All of Europe
450,000,000,000 gallons
150,000,000,000 gallons
6, 400,000,000 gallons
170,000,000,000 gallons
Water Trivia: US needs 115,000,000,000 gals/day of drinking water

8. What Happens to Water That’s Not Consumed ?
Goes down the drain
Dirty
Smelly
Hidden }
OOS/
OOM
&
and becomes
wastewater

9. “OOS/OOM”
Out Of
Sight
Out Of
Mind

10. One Person, One Day: Flush Toilet Shower/Bath Brush Teeth Wash Hands
15 gal
35 gal
4 gal
6 gal
(5 gal x 3 )
JUNE
15, 2006
(2 gal x 2 )
(2 gal x 3 )
60 gallons/person*
* Range: gallons/person-day

11. Typical Family Wastewater
Total usage 14.5 billion gallons per day
Dishwasher
(2%)
Kitchen Sink (8%)
Bathroom Sink (11%)
Bathing (20%)
Washing
Clothes (26%)
Toilet (33%)

12. What Happens to the Wastewater From Each Source?
Goes down a DRAIN
Where does the drain pipe lead?
Connects with other drains
Series of house pipes
Usually in the basement

13. Where Does It Go from There?

14. Where Does It Go from There?
S E W E R S

15. What is a SEWER? Series of pipes Below ground Conveys wastewater
Sewer has access points
House connections
Manholes

16. What We Should NOT Put Into Sewers ?
Paints
Solvents
Pesticides
Storm water
Oil
Gasoline
Plastics
Grease
Paint
Thinner

17. Why Not? Damage Sewers Corrosive Explosive Fire Block Sewers
Difficult to remove
Create odors
Overload Treatment Plant Reduce Capacity

18. DAMAGED SEWERS

19. For Example: Blocked Sewer

20. Where Should We Put Them?
Special Disposal Places
(check with Erie County or local Town officials)

21. HOUSEHOLD WASTE DISPOSAL
Erie County Household Hazardous Waste Drop-Off Day
Contact: (716) Or

22. Wastewater Flow in Sewers
Why is the sewer pipe tilted downward?
Water flows by gravity
From high point to low point
Have you ever seen water run uphill?

24. How Do We Get Wastewater Up a Hill ?
Sewer
Pump
Pumped
Wastewater
(Uphill)
Gravity
Wastewater Flow
(Downhill)
Hill
It needs to be PUMPED !

25. What is Sewer Pipe Made Of ?
Clay
Not Used - Old Pipe
Metal
Special Cases
Concrete
Larger Lines
Plastic
New- Most Common

26. Does one size sewer pipe fit all places
Sewer Pipe Size
Does one size sewer pipe fit all places NO
Pipe size is increased as more wastewater is introduced from additional homes 6” 8”
10”
12”
16”
20”
24”
30”
36” +

27. No! Can You See Sewer Pipes ? How Do You Know They Are There ? Manhole
Covers
Streets
Sidewalks
Private Property
Where

28. Can You See Sewer Pipes ?
Look for the connection from your house to the sewer. Look for your Cleanout,
it’s usually in you lawn.

29. Manholes - Why Do We Need Them ?
Provide access to sewers to
Look at
Fix
Clean
Monitor/sample
Join pipes
Change direction/ pipe size/slope
Provide venting

30. Sewer View From Above

31. Sewer View From Above 14” 12” 8” 8” 12” Increasing Pipe Size
Manhole
12”
Increasing Pipe Size
Joining
Pipe 8”
Manhole
Manhole
Changing Pipe
Direction 8”
12”
Increasing
Pipe Size

32. What Happens at a Wastewater Treatment Plant ?
Dirty water (called wastewater or sewage)
is cleaned….HOW?
Through treatment process by

33. But Why Send to a Treatment Plant Why Not Discharge to a River Or Lake

34. Why Not Discharge to a River or Lake?
River/Lake
Untreated wastewater will make humans sick
Untreated wastewater will kill fish and other aquatic life.
Impacts water quality

35. Why Not Discharge to a River or Lake?
Major concern –
BACTERIA/HEALTH
&
LOW OXYGEN LEVEL

36. Why Not Discharge to a River or Lake?
Bacteria/pathogens are harmful
Humans
Fish
Low Oxygen Level
Fish cannot survive

37. Wastewater Treatment Plants
Sewers discharge to wastewater treatment plants (WWTPs)
WWTPs remove
Bacteria/Pathogens
Organic matter
Solids
WWTPs discharge
Cleaner water
BUT HOW?

38. Wastewater Treatment Plant Summary
Steps 1 2 3
Bar Screen
Grit Tank
Solids Settling 5 4
Disinfection
Biological Treatment
Chlorine or
Ultraviolet
Clean
Water

39. Step 1: Bar Screens

40. Bar Screens

41. Step 2 - Grit Removal Grit can be: Egg shells Coffee grinds Nut shells
Seeds
Sand
Pebbles
Pits

42. Grit Tank

43. Step 3 - Solids Settling

44. Step 3 - Solids Settling Settling Tank Removes Solids from Wastewater
Solids can be:
Food
Poop

45. Solids Settling - Circular Clarifier

46. Solids Settling - Circular Clarifier

47. Step 4 - Biological Treatment
Aeration tank removes soluble organic material from wastewater
Hungry bugs eat organic material (food)
Clean water is left

48. Aeration Tank

49. (UV) Ultraviolet Bulbs
Step 5 - Disinfection
Clean
Effluent
Water
Chlorine Contact
Tank
Chlorine
Disinfection removes bugs from clean water before discharge
Chlorine or ultraviolet light kills bugs
Clean
Effluent
Water
(UV) Ultraviolet Bulbs
-OR-

50. Disinfection (chlorine contact)

51. Disinfection (Ultraviolet)

52. Wastewater Treatment Plant Summary
Steps 1 2 3
Bar Screen
Grit Tank
Solids Settling 5 4
Disinfection
Biological Treatment
Chlorine or
Ultraviolet
Clean
Water

53. But What Do We Do With The Solids Collected?
Steps 1 2 3
Bar Screen
Grit Tank
Solids Settling 5 4
Disinfection
Biological Treatment
Chlorine or
Ultraviolet
Clean
Water

54. Dewatering Why? - To reduce amount of water in solids
- To reduce disposal volume
- More water in solids = more cost $$$
Dewatering

55. Primary Clarifier Solids Final Clarifier Solids
Plant Solids
Primary Clarifier Solids
Final Clarifier Solids
Anaerobic
Digester
Solids Dewatering
To Landfill

56. THE FINAL RESULT – CLEAN WATER & HEALTHY ENVIRONMENT

57. THE END
ECDSM