Chapter 5 | Water and Waste Management

Question 1

Describe the three types of water and how each is used and handled

Answer 1

1. Potable (treated water safe for human consumption. Municipal water, wells, water buffalo)
2. Black water (contaminated)
3. Gray water (No human waste. Flushing toilets, Fire suppression, Irrigation [with permit])

Question 2

Describe the four filters

Answer 2

1. Sand (reduces turbidity)
2. Fine filter (removes iron and manganese)
3. Activated charcoal (removes taste and odor)
4. Reverse osmosis (removes most dissolved solids)

Question 3

What is water hardness?

Answer 3

Dissolved minerals, primarily calcium and magnesium

Question 4

What are the (5) problems associated with water hardness?

Answer 4

1. Formation of scale on water fixtures
2. Mineral deposits in water heaters
3. Increased detergent usage
4. Formation of soap curds
5. Yellowing of linen

Question 5

How does a water softener work?

Answer 5

As water passes through a bed of resin, the calcium and manganese in the water trade places with the sodium on the resin. To recharge, the bed is flooded with concentrated sodium brine

Question 6

Describe the (2) water distribution systems

Answer 6

1. Upfeed: water enters at ground level, travels up to where it is needed
2. Downfeed: water pumped to a tank at the top and pressure created by height of water in tank

Question 7

What are the advantages associated with circulating pump distribution systems?

Answer 7

Provide instant hot water to all fixtures
Compared to large pipes: uses smaller pipes
Compared to small pipes: it provides constant pressure

Question 8

What are the disadvantages associated with circulating pump distribution system?

Answer 8

They generally cost more to operate (maintenance/energy costs)
They have higher heat losses through the pipe walls

Question 9

Describe vibration noise (cause, problem, solution)

Answer 9

Cause: pump makes vibrating (machine noise)
Problem: Noise transmitted to sleeping rooms
Solution: cut the pipe and add and connect it with a heavy-duty rubber sleeve

Question 10

Describe water hammering (cause, problem, solution)

Answer 10

Cause: happens when an electric valve shuts off too quickly and a pressure wave is sent through the plumbing
Problem: can crack the water heater and joints in piping
Solution: Insert a vertical piece of capped pipe going up from the water pipe

Question 11

Describe pipe expansion (pipe creak) (cause, problem, solution)

Answer 11

Cause: change in temperature in the pipe
Problem: noise
Solution: Insulate the pipes to keep them at a constant temperature, absorbing some of the noise

Question 12

What are the two types of sewers and what do they handle?

Answer 12

1. Sanitary sewer (waste water)

2. Storm sewer (rain water)

Question 13

How would large amounts of rain water in a sanitary sewer impact a waste treatment plant?

Answer 13

Reduces amount of time water spends in the waste treatment plant so you end up flushing raw sewage

Question 14

What are the two components of a septic system and their function?

Answer 14

1. Septic tank: allows solids to settle out and liquid to flow to the leech bed
2. Leech bed: series of perforated pipes surrounded by gravel which purifies the waste

Question 15

What is the best way to reduce smell coming from a sewage lagoon?

Answer 15

Aerate it

Question 16

What is the function of drain vents and traps?

Answer 16

Drain vents prevent the water trap from being sucked dry.

P-traps use a plug of water to prevent odors and gasses from entering the building

Question 17

What is an indirect drain?

Answer 17

A drain that contains an air gap to prevent sewage backups and rats from getting in. Used in prep sinks

Question 18

What is the function of a grease trap and how does it work?

Answer 18

Grease traps allow grease to float to the top, solids to float to the bottom, and the filtered water in the middle runs out through a pipe