drainage system intro

THE DRAINAGE SYSTEM

GENERAL REGULATIONS

Danilo V. Ravina NAMPAP CEBU CHAPTER

Module 11

What is DRAINAGE SYSTEM?

Drainage System includes all the pipings within public or private premises which convey sewage or other liquid wastes to a legal point of disposal but does not include the mains of a public sewer system or a public sewage treatment or disposal plant.Sec 205.10 NPC 1999


The Drainage System is often known as the DWV System or Drainage, Waste and Vent System

It is composed of: Sanitary Drainage System the pipings that convey the discharge of water closets or fixtures having similar functions (containing fecal matter) with or without the discharges form other fixtures. Waste Drainage System the pipings that receive the liquid discharge from plumbing fixtures, other than water closets and urinals, and are free of fecal flow. Vent System the pipings installed to provide a flow of air to or from a drainage system or to provide a circulation of air within such system to protect trap seals from siphonage or back pressure. Storm Drainage System the piping system that receives clear water drainage from leaders, downspouts, surface run-off, ground water, subsurface water, condensate water, cooling water or other similar discharges and conveys them to the point of disposal. All sanitary waste must be excluded.


Storm Drain System

Waste Drain SystemSanitary Drainage System

Vent System


Vent Pipe a pipe or opening used for ensuring the circulation of air in a plumbing system and for relieving the negative pressure exerted on trap seals. Sec 223.3

Vent Stack the vertical vent pipe installed primarily for providing circulation of air to and from any part of the soil, waste of the drainage system. Sec. 223.4

House Drain is that part of the lowest horizontal piping of a plumbing system which receives the discharge from soil, waste and other drainage pipes inside of a building and conveys it to the house sewer outside of the building. Sec 209.6

House Sewer is that part of a plumbing system extending from the house drain at a point 0.60 meters from the outside face of the foundation wall of a building to the junction with the street sewer or to any point of discharge, conveying the drainage of one building site. Sec. 209.7

Soil Stack Pipe a vertical soil pipe conveying fecal matter and waste water. Sec. 220.21

Soil Pipe any pipe, which conveys the discharge of water closet, urinal or fixtures having similar functions, with or without the discharge from other fixtures to the building drain or building sewer. Sec. 220.22

GENERAL PARTS OF THE DRAINAGE SYSTEM


Waste Pipe a pipe, which convey only wastewater or liquid waste, free of fecal matter. Sec. 224.2

Septic Tank a water tight receptacle which receives the discharge of a sanitary plumbing system, designed and constructed to retain solids , digest organic matter through a period of detention and to allow the liquids to discharge into the public sewer or an approved private sewage disposal system. Sec. 220.7


Each plumbing fixture trap shall be protected against siphonage and back-pressure by means of vent pipes. Sec. 901

All horizontal piping shall run in practical alignment & at a uniform grade of not less than 2% (20 mm per meter) toward the point of disposal. Sec. 302

All horizontal piping shall be supported at sufficiently close intervals to keep them in alignment and prevent sagging. Sec. 315.2.1

Vertical piping shall be secured at sufficiently close intervals to keep the pipes in alignment. Stacks shall be properly supported at their bases. Sec. 315.1

Each plumbing fixture, except those with integral traps, shall be separately trapped by an approved type waterseal trap. Sec. 1001.1

A cleanout, easily accessible, shall be provided for inspection or cleaning of the pipe run. Sec. 706

GENERAL REQUIREMENTS FOR A PROPERLY DESIGNED DRAINAGE SYSTEM

Every building where plumbing fixtures are installed shall have a sewer service connection to a public or private sewer systems. Sec. 305.1


Catch Basin a receptacle in which liquids are retained for a sufficient period of time to allow settleable material to deposit. Sec. 204.3

Downspout the vertical portion of a rainwater conductor. Sec. 205.8

Leader a pipe connected from the building gutter to the downspout or conductor. Sec. 213.6

House Storm Sewer is the pipeline from the building to the public or street storm drainage system. Sec. 209.8

DRAINAGE DRAINS, TRAPS and VENTS


DRAINS


What is a Drain?

A Drain is a pipe, which carries ground and surface waters, storm water or wastewater into a building

drainage system.

The common types of drains are the floor drains and the roof drains.

The 2 types of drain connections are the direct drain connection and the indirect drain connection.


FLOOR DRAINS

Floor Drain a fixture providing an opening in a floor to drain water into a plumbing system; in homes, usually fitted with a deep seal trap.

Trench Drain a cast-in-place or preformed concrete trench usually covered with a grate that serves as both a drain and a collection point for run-off water or other liquid.


ROOF DRAINS

Roof Drain a drain designed to receive to receive water collecting on the surface of a roof and to discharge it into a leader or a downspout.

Scupper Drain an opening in a wall or parapet that allows water to drain from a roof.

Plantbox Drain


INDIRECT DRAIN

FUNNEL

Indirect Waste Pipe is a pipe that does not connect directly with the drainage system but conveys liquid wastes by discharging into a plumbing fixture, interceptor or receptacle directly connected to the drainage system. Sec. 210.1



Air Gap, Drainage the unobstructed vertical distance through the free atmosphere between the lowest opening from any pipe, plumbing fixture, appliance or appurtenance conveying waste to the flood level ream of the receptor. Sec. 202.6

Airbreak a physical separation, which may be a low inlet into the indirect waste receptor from the fixture, appliance or device indirectly connected.

TRAPS


What is a Trap?

A Trap is a fitting or device designed and constructed to provide, when properly vented, a liquid seal which prevents the backflow of foul air or methane gas without materially affecting the flow of sewage or wastewater through it.

The types of waterseal traps are:

1. P-trap is the most widely used for fixtures, common diameter sizes are 110mm (4), 63mm (2), 32mm (1-1/4) and 38mm (1-1/2).

2. Drum trap is used mostly for bathtubs. It has the advantage of containing a larger volume of water & discharging a greater volume of water than a P-trap.

3. Grease Interceptor / Grease Trap Grease interceptor is an interceptor of at least 3 cubic meter capacity to serve one or more fixtures and which is remotely located. Grease trap is a device designed to retain grease from one to a maximum of four fixtures.

4. House Trap/Running trap a device installed to prevent circulation of air between the drainage of the building and the building sewer.


51 102 mm

Trap seal the vertical distance or depth of liquid that a trap will retain, measured between the crown weir and the top of the dip of the trap.

Crown Weir the highest point of the bottom of the internal surface of the trap

Dip the lowest portion of the inside top surface of the channel through the trap

Waterseal Trap


LAVATORY P-TRAPP-TRAP

DRUM TRAP

HOUSE TRAP

TYPES OF TRAPS:


Lavatory P-TrapOrdinary P-Trap

Drum Trap

House Trap

TYPES OF TRAPS


TRAP ARM, FIXTURE DRAIN, FIXTURE BRANCH AND HORIZONTAL BRANCH


Each plumbing fixture, excepting those having integral traps , shall be separately trapped by an approved type waterseal trap. Not more than 1 trap shall be permitted on a trap arm*.

Trap Arm that portion of a fixture drain between a trap and the vent.


TRAP ARM


Horizontal Distance of Trap Arms

TRAP ARM DIAMETER

DISTANCE TO VENT(Except for Water Closets and similar

fixtures)

32mm (1-1/4) 760 mm

38mm (1-1/2) 1070 mm

51mm (2) 1520 mm

76mm (3) 1830 mm

102mm and larger

3050 mm

Each fixture trap shall have a protecting vent so located that the developed length of the trap arm from the trap weir to the inner edge of the vent shall be within the prescribed distance, but in no case less than two times the diameter of the trap arm.

TRAP ARM

The developed length between the trap of a water closet or similar fixture measured from the top of closet ring (closet flange) to inner edge of vent shall not exceed 1.8 meters.Danilo V. Ravina NAMPAP CEBU CHAPTER

FIXTURE DRAIN


FIXTURE BRANCH


HORIZONTAL BRANCH


GREASE TRAP


GREASE TRAP

When waste pretreatment is required, an approved type grease trap complying with the Code shall be installed in the wasteline leading from sinks, drains and other fixtures or equipment in establishments such as restaurants, cafes, lunch counters, cafeterias, bars and clubs, hotel, hospitals sanitarium, factory or school kitchens, or other establishments where grease may be introduced into the drainage or sewer system in quantities that can effect line stoppage or hinder sewage treatment or private sewage disposal.

A grease trap is not required for individual dwelling units or for any private living quarters.


Each plumbing fixture or piece of equipment connected to a grease trap shall be provided with an approved type Flow Control or restricting device installed in a readily accessible and visible location in the tailpiece or drain outlet of each such fixture.

Flow control Devices shall be so designed that the flow through such device or devices shall at no time be greater than the rated capacity of the grease trap.

TOTAL NUMBER OF FIXTURE CONNECTED

REQUIRED RATE OF FLOW IN LITERS PER

MINUTE

GREASE RETENTION CAPACITY IN KILOGRAM

1 76 18

2 95 23

3 132 32

4 189 45

GREASE TRAPS CAPACITY


Grease Trap:


UNDER COUNTER GREASE TRAP


GREASE TRAP

SIZING OF GREASE INTERCEPTOR:

S = M x W x R x F

Where:S = size of grease interceptorM = number of meals served at peak hourW = Waste Flow Rate: Use

- with dishwashing machine ------- 6 gallon flow (per meal/day)- without dishwashing machine -- 5 gallon flow (per meal/day)- single service kitchen ------------- 2 gallon flow (per meal/day)- food waste disposer --------------- 1 gallon flow (per meal/day)- hospital kitchen --------------------25 gallon/bed/day

R = Retention Time: Use- commercial kitchen waste dishwasher ----- 2.5 hours- single service kitchen, single serving ------- 1.5 hours

F = storage factors- For fully equipped commercial kitchen

8 hour operation: 116 hour operation: 224 hour operation: 3

- Single service kitchen: 1.5


DRAINAGE PIPING


Grade of horizontal excreta drainage piping

Horizontal drainage piping shall run in practical alignment and at a uniform slope of not less than 2% or 20 mm/m towards the point of disposal, provided that, where it is impractical due to the depth of the street sewer or to adverse structural features or to some irregular arrangements of affected building or structure to obtain a slope of 2% or any such pipe or piping 102mm or larger in diameter may have a slope of not less than 1% or 10mm/m when first approved by the Administrative Authority.


15 METERS

15 METERS

110 mm


3000 mm


VENTS AND VENT PIPING


What is a Vent?

A Vent is a pipe or opening that brings outside air into the plumbing system and equalizes the pressure on both sides of a trap to prevent trap seal loss.

Inadequate ventilation usually causes the loss of trap seal.

At sea level, atmospheric pressure is about 102 kPa (14.75 psi). Any difference between this pressure and the pressure on the discharge side forces the water seal into the direction of less pressure. Venting the discharge side of the trap to the atmosphere tends to equalize these pressures.


Causes of Trap Seal Loss:

Siphonage the withdrawal of a liquid from a trap due to a suction caused by liquid flow in a pipe without proper ventilation.

1. Direct or Self siphonage

2. Indirect or Momentum siphonage

Back Pressure or Back Siphonage pressure developed in opposition to the flow of liquid in a pipe due to friction, gravity or some other restriction to the flow of the conveyed liquid.

Evaporation occurs when a fixture is not used for a long time.

Capillary Attraction a foreign object lodged in the trap causes loss of trap seal by capillary action by acting as a wick.

Wind Effect


Causes of Trap Seal Loss:


What are the Types of Vents?

Soil and Waste Vent

Main Vent

Individual Vent or Back Vent

Unit Vent

Circuit Vent or Loop Vent

Relief Vent

Yoke Vent

Wet Vent

Looped Vent

Local Vent

Utility Vent


HORIZONTAL PIPING: HANGERS AND SUPPORTS

Horizontal pipes shall be supported at sufficiently close intervals to keep them in alignment and prevent sagging.

PIPE MATERIAL HORIZONTAL SUPPORTS AND HANGERS

CAST IRON SOIL PIPE supported at not more than 1.50 meters and shall be placed within 0.45 meters of the hub or joint. for pipes more than 1.50 meters in length, may be supported at not more than 3 meters interval

SCREWED PIPE At 3 meter interval for piping 19mm in diameter and smaller and 3.60 meters interval for pipings 25mm and larger in diameter.

PLASTIC PIPE shall be supported by stiff metal or wood backing with hangers in its entire length for pipes 38mm diameter and without backing but with spaced metal hangers at approved spacing for larger-size spacing.

IN GROUND Piping buried in the ground shall be laid in a firm bed for its entire length, except where concrete cradle support is provided.

LEAD PIPE Shall supported by stiff metal or wooden backing for its entire length with hangers properly spaced.


VERTICAL PIPING: SUPPORTS

Vertical piping shall be secured at sufficiently close intervals to keep the pipes in alignment and to carry its weight and contents.Stacks shall supported at their base.

PIPE MATERIAL SPACING OF PIPE SUPPORTS

CAST IRON SOIL PIPE Bell & spigot and hubless pipe shall be supported at every storey or closer

SCREWED PIPE Iron Pipe Size (IPS) shall be supported .

COPPER TUBING Shall be supported at its storey or at maximum intervals of 3 meters on center.

LEAD PIPE shall be supported at intervals not exceeding 1.20 meters at centers with a rigid verticalback-up.

PLASTIC PIPE Shall be supported at every 1 meter interval.


PIPE COLOR CODING


IDENTIFICATION OF PIPING BY COLOR

MATERIAL PIPED PIPE COLOR

Acetylene Orange

Acid Yellow

Air High pressure Yellow

Air Low pressure Green

Ammonia Yellow

Argon Low pressure Green

Blast Furnace Glass Orange

Carbon Dioxide Red

Gasoline Orange

Grease Orange

Helium Low pressure Green

Hydrogen Orange


Nitrogen Low pressure Green

Oxygen Orange

Oil Orange

Steam High pressure Yellow

Steam Low pressure Yellow

Tar Orange

Producer Gas Orange

Liquid Petroleum Gas Orange

Vacuum High Orange

Water Boiler Feed Yellow

Water Cold Green

Water Distilled Green


IDENTIFICATION OF PIPING BY COLOR


Water Fire Service Red

Water Hot Yellow

Water Low pressure (Excl. of Fire Service)

Green

Water High pressure (Excl. of Fire Service)

Yellow

Water Treated Green

Oil and Water (For Hydraulic System)

Green

Oil and Water (For Hydraulic System)

Orange


END OF PRESENTATION


drainage system intro

Documents

waste drainage system

storm drainage system

piping system

dwv system

public sewer system

sanitary plumbing system

clear water drainage

drainage systemdanilo