Construction: storage reservoir

INSERT YOUTUBE LINK: https://www.youtube.com/watch?v=Ng_s2ErvPqk&t=58s
The storage reservoir layer holds and directs the stormwater into the underlying/native soils. The LID facilities, if applicable, should be filled with uniformly graded, washed stone (20 mm – 50 mm) that provides 30 to 40% void space.

Construction steps:

1. Backfill material from outside of the LID facility to avoid compaction and sediment entering the facilities. Use a slinger truck if possible.
2. Place the material to the elevation and thickness as per the design specifications.

Key Inspection Points:

• Material arrival to the site:
  • Check chain of custody
  • Verify it meets specifications as per design
  • Verify no debris or fines within the aggregate (it’s a washed stone)
• Granular material should be 19 - 50 mm clear stone or as per design. See Aggregates for further details.
• Installed aggregate is at the correct elevation as per design.

Mistakes to Avoid:

• Accepting material that does not meet design requirements and specifications.
• Installing material with heavy equipment from the inside of the LID facility
• Installing frozen aggregate. Do not install frozen aggregate
• Leaving heavy equipment (excavator) for long periods of time within the LID facility.

For more guidance on materials specifications, refer to Aggregates, OPSS aggregates and (Ontario Provincial Standards, 2013)

An underlying bed filled with aggregate or other void-forming fill material that temporarily stores stormwater before infiltrating into the native soil or being conveyed by an underdrain pipe.

Low Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting.

Soil, sand and minerals washed from land into water, usually after rain. They pile up in reservoirs, rivers and harbors, destroying fish-nesting areas and holes of water animals and cloud the water so that needed sunlight might not reach aquatic plans. Careless farming, mining and building activities will expose sediment materials, allowing them to be washed off the land after rainfalls.

Soil particles with a diameter less than 0.050 mm.

A broad category of particulate material used in construction, including sand, gravel, crushed stone, slag, recycled concrete and geosynthetic aggregates, and available in various particulate size gradations.

Gravel, or crushed stone of various size gradations (i.e., diameter), used in construction; void forming material used as bedding and runoff storage reservoirs and underdrains in stormwater infiltration practices.

A broad category of particulate material used in construction, including sand, gravel, crushed stone, slag, recycled concrete and geosynthetic aggregates, and available in various particulate size gradations.