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==Overview==
==Overview==
Integration of Low Impact Development (LID) best management practices (BMPs) into stormwater management (SWM) systems is widely advocated to better address the potential stormwater-related impacts of urbanization on the health of receiving waters. A substantial amount of guidance is available on the planning and design of LID BMPs ([https://sustainabletechnologies.ca/app/uploads/2013/01/LID-SWM-Guide-v1.0_2010_1_no-appendices.pdf CVC & TRCA, 2010)<ref> CVC and TRCA. 2010. Low impact Development Stormwater Management Planning and Design Guide. Version 1.0. https://sustainabletechnologies.ca/app/uploads/2013/01/LID-SWM-Guide-v1.0_2010_1_no-appendices.pdf</ref> and their construction ([https://cvc.ca/wp-content/uploads/2013/03/CVC-LID-Construction-Guide-Book.pdf CVC, 2012])<ref> CVC. 2012. Low Impact Development Construction Guide. Version 1.0. https://cvc.ca/wp-content/uploads/2013/03/CVC-LID-Construction-Guide-Book.pdf</ref> and some municipalities and conservation authorities commonly require them to be a part of new SWM systems.
However, even with sound design, LID BMPs may not provide the intended level of treatment if they
are not installed properly or protected from damage during construction. Experiences with early
applications have shown that failures are often due to:
Practices not being constructed as designed or with specified materials;
Lack of erosion and sediment controls (ESCs) during construction; and/or
Lack of rigorous inspection prior to assumption.
A 2009 survey of stormwater BMPs in the James River watershed (Virginia) by the Center for
Watershed Protection found approximately half (47%) of the 72 BMPs deviated in one or more ways
from the original design, or were receiving inadequate maintenance (CWP, 2009). Similar results have
been revealed from surveys of stormwater detention ponds in Ontario (Drake et al., 2008; LSRCA,
2011), highlighting the need for thorough inspections of BMPs prior to assumption and a proactive
approach to stormwater infrastructure operation and maintenance.
Therefore, it is important to conduct timely inspections during construction and detailed inspection
and testing prior to assumption to ensure that LID BMPs are:
Built according to approved plans and specifications;
Installed at an appropriate time during overall site construction and with protective measures
to minimize risk of siltation or damage; and
Fully operational and not in need of maintenance or repair at the time of assumption by the
property owner or manager.
Like all stormwater BMPs, LID practices are designed to retain pollutants carried by urban runoff and
all have a finite capacity to perform this function in the absence of maintenance, until their treatment
performance declines or they no longer function as intended. Their functional and treatment
performance will only be sustained over the long term if they are adequately inspected and
maintained. Under the Ontario Water Resources Act, provincial approvals for SWM facilities and BMPs
(i.e., Ontario Ministry of the Environment and Climate Change’s Environmental Compliance Approvals
process) typically make the property owner responsible for all inspection and maintenance tasks and
associated record keeping (Zizzo et al., 2014). A proactive, routine inspection and maintenance
program will also:
==LID Practices' Inspection & Maintenance==
==LID Practices' Inspection & Maintenance==