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Chapter 7
Construction BMPs
• Final Stabilization and Long-Term Stormwater Management
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The SWMP should describe the practices used to achieve final stabilization of all disturbed areas
at the site and any planned practices to control pollutants in stormwater discharges that will occur
after construction operations have been completed at the site.
Final stabilization practices for obtaining a vegetative cover should include, as appropriate: seed
mix selection and application methods; soil preparation and amendments; soil stabilization
practices (e.g., crimped straw, hydro mulch or rolled erosion control products); and appropriate
sediment control BMPs as needed until final stabilization is achieved; etc.
Final stabilization is reached when all ground surface disturbing activities at the site have been
completed, and uniform vegetative cover has been established with an individual plant density of
at least 70 percent of pre-disturbance levels, or equivalent permanent, physical erosion reduction
methods have been employed.
• Inspection and Maintenance. The SWMP should describe the inspection and maintenance
procedures implemented at the site to maintain all erosion and sediment control practices and other
protective practices identified in the SWMP in good and effective operating condition. UDFCD
recommends providing an inspection checklist for the project.
3.2 Inspections
Routine and post-storm inspections of BMPs are essential to identify maintenance necessary for the
BMPs to remain in effective operating conditions. The frequency of inspections is typically influenced by
multiple factors including the weather, the phase of construction, activities on site, and the types of
BMPs. Checklists and other forms of documentation are also important to meet the requirements of a
construction stormwater permit.
3.2.1 Inspection Frequency
In Colorado, the CDPS General Permit requires documented inspections on a biweekly basis and within
24 hours of a storm event, with some limited, temporary exceptions for inactive sites. UDFCD
recommends spot-checking BMPs every workday. This is typically reasonable to achieve and can help to
ensure that the BMPs remain in good working condition. For example, vehicle tracking of sediment onto
the roadway is a common problem that often requires maintenance more frequently than weekly. Curb
socks, inlet protection and silt fence are other BMPs that are prone to damage and displacement, also
benefiting from more frequent inspections.
When the site or portions of the site are awaiting final stabilization (e.g., vegetative cover), where
construction is essentially complete, the recommended frequency of inspection is at least once every
month. Be sure that this change is documented and in accordance with relevant permit requirements prior
to reducing the inspection schedule.
When snow cover exists over the entire site for an extended period, inspections are not always feasible.
Document this condition, including date of snowfall and date of melting conditions, and be aware of and
prepare for areas where melting conditions may pose a risk of surface erosion.
November 2010 Urban Drainage and Flood Control District 7-9
Urban Storm Drainage Criteria Manual Volume 3