Changes

A liner is sometime incorporated into non-infiltrating practices such as [[stormwater planters]], or has also been applied in [[permeable paving]] installations where seperation from the native soils and groundwater was required.  

An impermeable liner is incorporated into non-infiltrating practices such as [[stormwater planters]], and may be applied in [[permeable pavements]] installations where separation from the native soils and groundwater is required.  

*Waterproof containment can be created using a plastic membrane/liner (HDPE or EPDM are common materials).

*Waterproof containment can be created using concrete or a plastic membrane/liner (HDPE or EPDM are common materials).

**When the membrane is being used directly in the ground, punctures from stones can be prevented by compacting a layer sand (30  - 50 mm) over the soil prior to installing the membrane.  

**When the membrane is being used directly in the ground, punctures from stones can be prevented by compacting a layer sand (30  - 50 mm) over the soil prior to installing the membrane.  

**Alternatively, a manufactured cushion fabric (geotextile) can be employed for this purpose.   

**Alternatively, a manufactured cushion fabric (geotextile) can be employed for this purpose.   

**The top surface of the membrane must also be protected from stone and gravel being used for inside the BMP. Again, sand or a cushion fabric may be used.  

**The top surface of the membrane must also be protected from stone and gravel being used for inside the BMP. Again, sand or a cushion fabric may be used.  

*When a pipe is used to provide drainage from the BMP cell, a 'pipe boot' should be sealed to both the pipe and the liner to prevent leaks.     

*When a pipe is used to provide drainage from the practice to an outlet structure or storm sewer, a 'pipe boot' or flange should be sealed to both the pipe and the liner to prevent leaks.     

[[Category:Materials]]

[[Category:Materials]]