Changes

*''Importance of construction inspections''

*''Importance of construction inspections''

*''Contractor familiarity''

*''Contractor familiarity''

*''What you can expect from STEP guidance: practical advice, specific to LID, practical advice on how to ensure successful construction''

*''What you can expect from STEP guidance: practical advice, specific to LID, on how to ensure successful construction''

*''LID types and construction sequencing''

==Construction stages==

 

==Construction stages and LID types==

STEP divides the construction process for LID practices into five over-arching stages:   

STEP divides the construction process for LID practices into five over-arching stages:   

#[[Sub-surface components]]

#[[Sub-surface components]]

#[[Finishing grades: inlet, outlet, and surface layer]]

#[[Finishing grades: inlet, outlet, and surface layer]]

#[[Post-construction]]]

#[[Post-construction]]

 

Stages 1-3 and 5 of the LID construction process are fundamentally similar for all '''surface-level LID''' types (bioretention, bioswales, enhanced grass swales, permeable pavements, infiltration chambers, infiltration trenches, soakaways, etc.). To illustrate, STEP's recommended processes for excavation do not differ depending on the practice type. Excavation is excavation, whether it is for a bioretention garden or a permeable pavement parking lot. On the other hand, stage 4 sub-tasks will vary substantially from LID type to LID type, as do some sub-tasks in stage 3. The following gives a brief description of each over-arching stage and links to the page dedicated to each construction stage.

For this reason, Stages 1-2 and 5 of the LID construction process are fundamentally similar for all '''ground-level LID''' types. To illustrate, STEP's recommended processes for excavation do not differ depending on the practice type. Excavation is excavation, whether it is for a bioretention garden or a permeable pavement parking lot. On the other hand, stage 4 sub-tasks will vary substantially from LID type to LID type, since the construction processes for installing the surface of an LID practice will differ depending on whether the practice is vegetated or not. Some sub-tasks in stage 3 will also vary. For example, permeable pavements often require compaction of sub-surface storage layers. The following sections give a brief description of each over-arching stage and links to the page dedicated to each construction stage.

'''Green roofs, blue roofs, and rainwater harvesting systems have specific construction requirements. One day we will write guidance for these LID practices as well'''

'''Green roofs, blue roofs, and rainwater harvesting systems have specific construction sequences that differ from the main sequence described above. One day we will write guidance for these LID practices as well.'''

==Pre-construction==

==Pre-construction==

Pre-construction activities set the stage for the successful construction of '''an LID''' practice. The [[Pre-construction|pre-construction]] page gives guidance on:  

Pre-construction activities set the stage for the successful construction of an LID practice. The [[Pre-construction|pre-construction]] page gives guidance on:  

*design verification and site walk-through

*design verification and site walk-through

*LID construction notes

*LID construction notes

==Sub-surface components==

==Sub-surface components==

Many LID practices rely on sub-surface features--gravel storage reservoirs, liners, underdrains, monitoring wells, etc.--to function. The construction process for sub-surface components works from the ground up. While some LID practices include all the sub-surface components listed below, most designs will not include one or more of these layers. Also, permeable pavement types can have different construction requirements at this stage, mostly regarding compaction of sub-surface layers.  

Most LID practices use sub-surface features--gravel storage reservoirs, liners, underdrains, monitoring wells, etc. The construction process for sub-surface components works from the ground up. While some LID practices include all the sub-surface components listed below, most designs will not include one or more of these layers. Permeable pavements can have different construction requirements at this stage, mostly regarding compaction of sub-surface layers. '''Installing infiltration chambers also requires guidance specific to that LID type.''' 

The '''backfill granular, utilities, and pipes / [[sub-surface components]]''' page gives guidance on:  

The '''backfill granular, utilities, and pipes / [[sub-surface components]]''' page gives guidance on:  

==Finishing grades and surface layer installation==

==Finishing grades and surface layer installation==

This construction stage differs between LID practice type. The finishing grades and surface layer installation page has guidance for vegetated LIDS (bioretention, bioswales, enhanced grass swales, and vegetated filter strips; can also include infiltration chambers/trenches/soakaways, depending on the design) and permeable pavements.

This construction stage differs between LID practice type. The finishing grades and surface layer installation page has guidance for vegetated LIDs and non-vegetated LIDs (i.e., permeable pavements). In many cases the surface of infiltration systems will be traditional asphalt, concrete, or pavers; STEP does not provide guidance on installing non-permeable surfaces.

*soil media installation and soil amendment

*soil media installation and soil amendment