drainage Flashcards
what is stormwater drainage
Systems that are put in place to help prevent floods by diverting rainwater into nearby waterways that flow into underground pipes which flows to streams,ponds or reservoirs
what are Foundation drains (1.)
Foundation drains are pipes that are installed under your foundation or basement floor to collect water and move it off-site to prevent your basement from filling with water.
Gutter(2.)
a shallow fixed beneath the edge of a roof for carrying off rainwater.
Downpipe (3.)
downpipe is a pipe that is used to direct rainwater away from a building, typically from roof guttering to a drainage system. It is sometimes also referred to as a downspout, drain spout, roof drain pipe or leader
Catchpit (4.)
A Catchpit is essentially an empty chamber with an inlet pipe and an outlet pipe set at a level above the floor of the pit. Any sediment carried by the system settles out whilst in the Catch-Pit, from where it can be periodically pumped out or removed.
why install a French drain (5.)
French drains are primarily used to prevent ground and surface water from seeping into building foundations, however, are many reasons why people will install a French drain to redirect surface and ground water. These drains are often used to remove excess water from low areas, or extremely wet areas of the property.
channel /trench drain (6.)
A trench drain (also channel drain, line drain, slot drain, linear drain or strip drain) is a specific type of floor drain containing a dominant trough- or channel-shaped body. It is used for the rapid evacuation of surface water or for the containment of utility lines
Drywell (7.)
a shaft or chamber constructed in the ground in order to aid drainage, sometimes containing pumping equipment.
a.k.a. dry hole.
storm sewer (8.)
a sewer built to carry away excess water in times of heavy rain; a storm drain.Storm drain inlets are typically found in curbs and low-lying outdoor areas.
what does a Sump pump(9.) do
he sump pump’s job is to pump the water out of the pit and away from the building so the basement or crawlspace stays dry.
What is grey water
the relatively clean waste water from baths, sinks, washing machines, and other kitchen appliances.
A grey water system usually consist of
- ________
- _______
- _______
- _______
- _______
- Plumbing system- made out of pipes and valves to capture the grey water
- surge tank - to temporarily hold large drain flows (WM/ Bath)
- filter- to remove particles which could clog the irrigation system
- pump - to move water from the surge tank to the irrigation system
- irrigation system - to distribute water to plants
rainwater harvesting
Rainwater harvesting (RWH) is the collection and storage of rain, usually collected from roofs (via gutters)
rainwater harvesting vs stormwater harvesting
rainwater harvesting is collected from roofs or elevated surfaces where as stormwater harvesting is collected from creeks, drains, roads or any other land surfaces
name the 8 steps of the complete system for rainwater
Catchment surface I First Flush I Inlet filtration I Calming Inlet I Storage I Distribution I Filtration I Use
pros and cons to above-ground storage of rainwater (at least 3)
pros
- easy inspection (crack and leaks)
- gravity feed
- raised to increase water pressure
cons
- space
- easily damaged
- failure can be dangerous
- prone to attack from weater
pros and cons to underground storage of rainwater (at least 2p 3c)
pros
- ground support= thinner walls= cost less
- un-obstructive
cons
- hard to detect leaks
- requires pump
- possible contamination (groundwater)
- roots or rising groundwater = damage
- not easy to drain or clean
Grey and black water: differences and similarities
Greywater
– Refers to all waste water with the exception of soil water – aka ‘Blackwater
’
2. Blackwater / Soil water
– Water drained from toilet
– Greywater & Blackwater should never be drained from the same pipe/drainage system
• Both greywater & blackwater are connected to the sewer system, usually via PVC
pipes.
• Sizes usually between 30mm and 50mm ⌀ (except for toilet)
• The sewerage water runs to a sewerage plant where the soiled water is treated and
released back into our natural resources.
• All drainage pipes are installed at an angle for better water flow
• Gravity carries waste water to sewerage sytem
Sanitary Fixtures
– Refers to ‘permanent’ sanitary ware
– Toilets, hand-wash basins, baths & showers
– Some can be supplied with recycled greywater e.g. toilets for flushing
Sanitary Appliances
– Refers to temporary sanitary ware
– Kitchen sinks, dishwashers & washing machines
– Supplied with clean water
Water closets / Toilets
- Manufactured as ‘Wash down’ pans or ‘Siphonic’ pans
- Both have a visible water seal – the water you see in the bowl
- Water seal is either a ‘P’ or ‘S’ trap
- Minimum of 100mm ⌀
- Drainage pipe is bigger because of the amount of water required to flush a toilet
Wash Down Pans
• Displaces the waste water with fresh water from
the cistern
• Most reliable
• Noisiest
Siphonic Pans
• As water exits through the trapway, it displaces
the air inside to form a vacuum.
• Waste is essentially sucked out
• Clogs more easily
The Trap
P-Trap S-Trap Bottle-Trap
– Both sanitary fixtures & sanitary appliance are connected to the drainage system via
protective water seal known as a Trap
– The trap prevents any possibility of health hazards & unpleasant odours from entering
the building
– Water is trapped in the P, S or Bottle shape and is replaced with fresh water each time the
fitting is used
– Traps and drain
– Most common types:
• P-Trap > towards wall outlet
• S-Trap > towards floor outlet
• Bottle-Trap > towards wall outlet
DRAIN RUNS
• Below ground waste pipes
• Shortest route from the highest point
– where waste water needs to be collected public sewer
connection / septic tank / conservatory tank
• As straight as possible with a continuous fall
• Collects branch drains along the way
DRAIN FALLS
• Waste pipes uses gravity to transport water to the main sewerage line
• Gradient between 1:5 and 1:60
• Shallow drains that only have 300mm of ground cover should be
protected by a concrete slab 100mm above
• Drains under houses should be avoided!
POINTS OF ENTRY
- Ground floor waste pipes
* Discharges into a soil pipe or trapped gully
GULLY
- AKA trapped gully
- Connects directly to the drain pipe via 100mm ⌀ drain pipe
- Prevents possible flooding of appliances by draining water
RODDING EYES (CLEANING EYES)
• Provides access for inspection of a drain pipe run should it
get blocked
• Vertical sloping pipe that extends up to ground level
• Has an air-tight cap, concrete surround and cast-iron lid @
ground level
• Located at the highest point of a drain pipe
INSPECTION EYES
• Found upstream from connection of drain to a connecting
sewer
• Necessary at every drain junction
SEPTIC TANK
• Built below ground
• Comprised of two chambers divided by a wall
• Built below ground
• Separates solids and liquids
– Top layer = Scum
– Bottom layer = Sludge
• The Middle Layer = semi clear liquid which is then
drained into an absorption field – i.e. the ground
