Design verification and site walk-through

Design verification and site walk-through

In preparation for finalizing the designs the project manager (PM) should conduct a walk-through of the site to verify that the designs match site conditions. This site walk-through is a critical step in the transition from design to construction and aids future pre-bid or pre-construction meetings. The PM should think carefully about how a contractor will be able to build the LID practice, determine if the design drawings and construction notes address specific LID construction requirements, and whether they contain inaccuracies or are missing detail. When field verifying the drawing set, Table X identifies details key points and considerations.

Design verification points and key considerations

Verification point	Key considerations
Adjacent land uses	- Have land uses changed while the design was in progress? Are there any planned land-use changes on adjacent properties and is their drainage connected to the site soon to be under construction? - Will it create dirty runoff that may flow onto the construction site or into the LID feature? - Is additional ESC required beyond what is marked in the ESC plan?
Contributing and receiving drainage areas	- Where is water coming onto the site and where is water leaving the site? - Are any environmentally sensitive areas downstream? - Are there any apparent changes while the design was in progress? If so, should these changes necessitate modifications to the design, particular ESC measures, etc.?
Seasonal maintenance operations	- Will winter snow storage and salt application impact the functionality of the LID feature?
Location of LID features	- Do the proposed LID locations match the site? -Does the footprint of the LID fit within the site constraints?
Existing and planned infrastructure / utilities	- Confirm accuracy of design drawings - Are there any unmarked utilities not detailed within drawing set?
Property boundaries and building foundations	- Confirm accuracy of design drawings - Do fence lines align with property boundaries?
Natural heritage features and existing vegetation	- Do the designs accurately capture existing natural heritage features? Which areas on the site should be protected during construction, and will these exclusion areas make the LID facility more difficult to construct? Where are the tree drip lines? - Are there any invasive species on the site which could colonize the LID practice?
Access, sequencing, staging, and constructability	- Where will the contractor access the site? - If applicable, where can materials and/or equipment be stored - What is the ideal construction sequence, and where could materials and supplies be stored during construction? - Do site characteristics constrain standard construction practices? Will it be a difficult job? - Do constructability issues require a field change or amendment to the tender?

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.

The portion of water precipitated onto a catchment area, which then flows as surface discharge from the catchment area past a specified point.

Water from rain, snow melt, or irrigation that flows over the land surface.