6 Drainage Systems Explained

Key Concepts

• Sanitary Drainage Systems
• Storm Drainage Systems
• Combined Drainage Systems
• Grease Traps and Interceptors
• Ventilation Systems
• Inspection and Maintenance

Sanitary Drainage Systems

Sanitary drainage systems are designed to remove wastewater from buildings. These systems include pipes, traps, and vents that carry waste to a treatment facility or septic system. The key components are:

• Pipes: Transport wastewater from fixtures to the main drain.
• Traps: Prevent sewer gases from entering the building by holding a small amount of water.
• Vents: Allow air to enter the system, preventing negative pressure that could siphon water from traps.

Example: A residential home with a plumbing system that includes pipes from sinks, toilets, and showers leading to a main drain that connects to the municipal sewer system.

Analogy: Think of a sanitary drainage system as a "waste disposal network" that safely removes waste from your home, similar to how a trash collection service removes garbage from your house.

Storm Drainage Systems

Storm drainage systems are designed to manage rainwater and surface runoff. These systems include gutters, downspouts, and underground pipes that direct water away from buildings to prevent flooding. Key components include:

• Gutters and Downspouts: Collect and direct rainwater from the roof.
• Drainage Pipes: Transport water away from the building to a storm sewer or natural drainage area.
• Catch Basins: Collect surface runoff and debris before it enters the drainage system.

Example: A commercial building with gutters and downspouts that direct rainwater into underground pipes leading to a storm sewer system.

Analogy: Consider a storm drainage system as a "water evacuation route" that quickly removes rainwater from your property, similar to how a drainage ditch prevents water from pooling in a field.

Combined Drainage Systems

Combined drainage systems handle both sanitary waste and stormwater in the same pipe network. These systems are common in older urban areas but can lead to overflow issues during heavy rain. Key components include:

• Combined Sewers: Pipes that carry both wastewater and stormwater.
• Overflow Structures: Devices that release excess water into natural water bodies to prevent flooding.

Example: An older city with a single pipe network that carries both household waste and rainwater to a treatment plant, with overflow structures in place to manage heavy rainfall.

Analogy: Think of a combined drainage system as a "dual-purpose highway" that handles both regular traffic and emergency vehicles, but may become congested during peak times.

Grease Traps and Interceptors

Grease traps and interceptors are devices used to capture and retain fats, oils, and grease (FOG) from wastewater. These devices prevent FOG from entering the drainage system and causing blockages. Key components include:

• Grease Traps: Small devices installed under sinks in commercial kitchens.
• Grease Interceptors: Larger devices installed outside buildings, often used in restaurants and food processing facilities.

Example: A restaurant with a grease trap installed under the kitchen sink to capture FOG before it enters the sewer system.

Analogy: Consider a grease trap as a "strainer" that filters out unwanted substances from your kitchen sink, similar to how a colander removes water from pasta.

Ventilation Systems

Ventilation systems are essential for maintaining proper airflow in drainage systems. These systems include vents that allow air to enter the pipes, preventing negative pressure that could siphon water from traps. Key components include:

• Roof Vents: Installed on the roof to allow air to enter the drainage system.
• Wall Vents: Installed in walls to provide additional ventilation.

Example: A residential home with roof vents that allow air to enter the plumbing system, preventing negative pressure and maintaining proper drainage.

Analogy: Think of a ventilation system as a "breather" that ensures your plumbing system has a steady supply of air, similar to how a chimney allows air to circulate in a fireplace.

Inspection and Maintenance

Regular inspection and maintenance are crucial for the proper functioning of drainage systems. Key activities include:

• Visual Inspections: Checking for leaks, blockages, and signs of wear and tear.
• Cleaning: Removing debris and buildup from pipes and traps.
• Testing: Conducting tests to ensure the proper functioning of vents, traps, and other components.

Example: A commercial building with a scheduled maintenance plan that includes regular inspections and cleaning of the drainage system.

Analogy: Consider inspection and maintenance as a "health check-up" for your drainage system, ensuring it remains in good working condition, similar to how regular medical check-ups keep you healthy.