Water Supply And Drainage Systems

Front 1

Hardness/Softness

Back 1

Hardness in water comes from minerals dissolved in ground water (mostly limestone), harmful to plumbing systems deposits can clog. Can cause problems with heat exchangers (in heating applications) by insulating pipes and can cause with detergents. Water is softened by zeolite (ion exchange) process.

Front 2

Lift (Water pressure)

Back 2

Lift is relationship between feet and psi.

1 psi = 2.33 feet

1 foot = .433 psi

Front 3

Downfeed system

Back 3

Downfeed system uses pumps to send water to tanks at top of building. Use gravity to supply fixtures.

Disadvantage is adds considerable weight to structure.

Front 4

Pneumatic Tank

Back 4

A system that uses a pressurized tank in the basement to compress air to act as spring to push water to fixtures (water cannot be compressed) takes up floor space and causes air to be dissolved in water.

Front 5

Tankless system

Back 5

System that uses one or more variable speed pumps, which constantly turn on and off or run at varying speed to provide sufficient pressure at building demand rate. Causes pumps to wear faster but require little space and no additional structure.

Front 6

Friction loss

Back 6

Friction loss is a function of pipe diamter and flow rate. Higher flow or smaller diamter pipe = increased pressure loss due to friction.

Front 7

Hot water systems

Back 7

Water heater: tank that is pressurized and rated in terms of volume and recharge. Heats water in tank and sends to fixtures.

Continuous loop system: hot water is continuously pumped through closed loop in building. Water in pipes do not cool when not in use but has small but steady heat loss.

Instantaneous heater: electric coil, small burner or heat exchanger heat cold water supply when hot water faucet is turned on.

Front 8

Thermal expansion

Back 8

Expansion in pipe due to thermal expansion.

Change in Length = Pipe length x material coefficient of expansion x (Final temperature minus original temperature). Pipe support should have rollers or be flexible to accommodate change in Length.

Front 9

Sanitary Waste

Back 9

Sanitary waste consists of soil lines (waste from toilets, urinals, etc) and waste lines (all other fixtures such as sinks and showers). Lines need to be vented to relieve pressure and break suction or siphoning action that could contaminate water supply.

Front 10

Sanitary vents

Back 10

Sanitary vents consist of three vents; soil stack, vent stack, and stack vent.

Soil stack: large pipe to which soil and waste lines go to, open out outside at top.

Vent stack: smaller pipe that is air intake for all fixtures, open at top separate from soil stack.

Stack Vent: section above highest fixture. The stack vent vents the soil stack. Minimum diameter for vent is 1 1/4 inch or half the size drain it serves, what ever is larger.

Front 11

Handicapped Access Restrooms

Back 11

Toilet stalls must enable person to exit stall so door must swing outward. Typically requires clear 5-0" swing 10" AFF. This is above ANSI 117.1 standards. Best seat height is 1'7" AFF so transfer is not uphill. Stalls less than 5' must have grab bars on each wall to turn around, also one grab bar behind toilet is preferred. Grab bars must be between 33-36 inch AFF.

Front 12

Handicapped Accessible Lavatories

Back 12

Rest rooms should have at least one lavatory with sufficient clearance underneath to fit wheel. Fixtures should have large level controls rather than small handles. Exposed hot water lines should be well insulated and mirror should be tilted so wheelchair can see.

Front 13

Handicapped Access drinking fountains

Back 13

Drinking fountains typically have two different heights used. One at 39" for abled bodies and one at 32"-34" for handicapped Access. Lower fountain to protrude as far as possible without interfering with traffic flow.

Front 14

Handicapped baths and showers

Back 14

Baths must be supplied with grab bars. Handicapped baths should have a seat, roughly wheelchair height or at least tub edge height. Elevating tub ehighr is good idea.

Showers with minimum curb height or no curb. Door 33" wide to roll wheelchair in. Flexible hose and nozzle for shower head. 5' clear space is best but 4' with shower seat is acceptable if 10" AFF is clear for front wheels and feet.

Front 15

Interceptors

Back 15

Designed to intercept grease, string, rags, etc from getting into system. Some places are required to have them such as restaurants as the grease could damage system or treatment facility. All interceptors have means to clean out material. NOT A TRAP

Front 16

Clean-outs

Back 16

Clean outs for systems are Y shaped segment of pipe with unscrewable pipe arm to access blockage. Required at building drain to sewer connection. Placed every 50 feet for pipes under 4" dia and 100 feet for pipes +4" and locations with direction changes greater than 45 deg.

Front 17

Man holes

Back 17

Similar to clean outs but for larger lines 10" dia and larger. Occur every 150ft and wherever a new line joins system. Provides access for inspection.

Front 18

Public sewer treatment

Back 18

Public sewer systems are treated at WWTPs before returning to nearest body if water. Uses settlement tanks, algea, and chemicals to clean water. Water is chlorinated and returned to water supply. Dried sludge is sent to landfill or used as fertilizer (not for residential or farming due to possible contamination)

Front 19

Storm Drainage

Back 19

Surface and storm drainage is Sept separate from sanitary waste to avoid any overflows at street or WWTP. Must design storm water runoff to recharge water table. Can use swales and catch basins to return runoff back to water table.

Front 20

Swale

Back 20

Swales are v-shaped sloping channels I'm grade that take surface runoff to places either collected or disposed of.

Front 21

Catch Basins

Back 21

Similar to manholes these have grated cap instead of plate. Placed at lowest point of Swale or depression to collect runoff and pass it into storm water drainage system into local lake or steam.

Front 22

Steel pipes

Back 22

Galv steel pioes, typically schedule 40 is most common. Joined mechanicall, threaded and joint compound or tape is applied to seal the minute cracks or gaps. Screwed into connecting collar. In drainage systems ends are often clamped together with rubber sleeve, steel jacket and two steel band clamps

Front 23

Copper pipes

Back 23

Typically used for supply piping. Does not rust and wall thickness are much thinner. 3 types K,L, and M. M is most common and thinnest walls. Copper pipes are joined together with solder called sweating, two pipes are soldered together with a sleeve. Can be reused, melt solder and reconnect

Front 24

Plastic piping

Back 24

Two types of plastic, PVC used for supply and ABS used for drainage. Does not rust, light weight and does not hold mineral deposits. CANNOT be used in exterior where exposed to sunlight. Connected to sleeve and solvent or plastic cement is applied. Cannot be reversed without cutting pipe.

Front 25

Waste water contamination

Back 25

Waste water must not be allowed to contaminate water supply. Faucets to never extend below sink edge and should have a minimum 2" air gap. Where siphoning could occur, vaccum seal must be installed.

Front 26

Fixture Unit (FU)

Back 26

A fixture Unit is an arbitrary unit used to describe the size of the pipe. Takes into account all fixtures in system being used at same time. Has a variable relation to GPM 1000 fu = 220 gpma but 2000 fu = 330 gpm