Credit 3.1: Minimize Site Disturbance
This credit applies to actions in order to minimize the amount of clearing, grading, and soil disturbance during construction on the site.
Where this credit applies
This credit applies to both whole site and shoreline/riparian development. It is particularly important for projects on sloping sites, sites with runoff from upland areas, sites with highly erodible materials, and bluff properties where slope failure risk is high.
This credit offers up to 5 base points.
Minimize site disturbance for undeveloped (greenfield) site:Base points
|Do not disturb soils and retain native vegetation over:|
|>70% of the site area*||5|
|50-69% of the site area||3|
|30-49% of the site area||1|
|Minimize site disturbance for previously developed site:||Base points|
|Limit development to previously developed portions of the site as much as possible and if available, protect any remaining soils and vegetation** from disturbance over:|
|>60% of the site area*||3|
|45-59% of the site area||2|
|20-44% of the site area||1|
*Site area is defined as:
- The lot area if your project involves the whole lot; or
- The riparian buffer (see Glossary), if your project is restricted to the shoreline/riparian area.
See “How to proceed” below.
How to proceed
Minimize site disturbance during planning, design, and construction phases of a project by doing the following:
- Locate buildings and hardscape surfaces on previously impacted areas of the site such as clearings, existing building footprints, or on areas that were going to be cleared anyway (e.g., to remove invasive species such as Himalayan blackberry).
- Minimize the amount of excavation and earthworks needed by fitting the building or landscape design to the site topography rather than flatten the site to fit the building or landscape.
- During construction, protect vegetation and native soil areas from disturbance and compaction by surrounding them with a secure 4 ft. fence of high visibility material.
- Restrict construction vehicle traffic to designated driveways/accesses to reduce damage to soils and vegetation. On small sites, this may mean parking offsite on a nearby road edge. Encourage carpooling.
- Designate specific staging areas for materials (gravel, lumber, etc.) in previously disturbed areas.
To attain this credit:
- Determine the applicable site area. If your project involves the whole lot, use the lot area defined by a property survey. If your project is just in the shoreline /riparian area, use the riparian buffer; the shoreline area that lies within the minimum riparian buffer/setback required by local regulations OR within 35 ft/10 m of the OHWM (measured as the horizontal distance landward of the OHWM), whichever is greater. Calculate the site area by multiplying the shoreline length along the OHWM by 35 feet (10 m) or by the width of the buffer/setback requirement by local regulations.
- Measure the portion of the site area where soil will be disturbed and vegetation removed to make way for the project.
- Calculate the percent of the site that will remain undisturbed and use that percentage to determine applicable points based on the table above.
Marine: Site design plans showing minimization of disturbance on the site and control of disturbance including sediment control measures. Other information on this site revealed that all disturbances would take place in the footprint of the structures and native vegetation removed would be used in the on site landscaping.
For more information
BC Ministry of Environment, 2012. Develop with Care: Section Three – Site Development and Management. http://www.env.gov.bc.ca/wld/documents/bmp/devwithcare/# Low Impact Development Centre (as of 2015) www.lowimpactdevelopment.org. Low Impact Development Technical Guidance Manual for Puget Sound. http://www.psp.wa.gov/LID_manual.php Soils for Salmon (as of 2015) www.soilsforsalmon.org. Soil Amendments (as of 2015) http://www.structuresoil.org Includes link to the Building Soil Manual.