Culverts are a critical asset that facilitate drainage and provide pathways for water to flow under roadbeds. Their purposes are to prevent roadway flooding, reduce erosion, and prevent roadway maintenance problems. More visible infrastructure such as pavement, bridges, and guardrails are often given more attention. However, smaller assets such as culverts are important assets to inspect due to their impact on pavement, and other structures above.
Culvert – A structure, including supports, erected over a depression or an obstruction such as water, highway, or railway. Having a track or passageway for carrying traffic or other loads. Having an opening measured along the centerline of the roadway less than or equal to 20 feet between copings of abutments or spring lines of arches, or extreme ends of openings for multiple boxes, pipes, or pipe arches.
Large Culvert – A culvert having an opening measured perpendicular to the centerline of the culvert greater than or equal to 5 feet or multiple pipes.
Why are Culverts Important?
Proper drainage is essential for pavement to maximize life expectancy and minimize maintenance. Usage over time along with environmental factors begin to wear on the structures. Underground assets that are not monitored are more likely to fail. Agencies need to conduct regular culvert inspections to proactively identify maintenance issues . Culverts can fail over time in a variety of ways, therefore regular inspections are necessary. Should a culvert be replaced, repaired or maintained? Previous documentation of the culverts condition will determine the culverts future. It is important to keep records up to date on all culverts to minimize failures and replacement cost. Replacing a culvert is a much larger expense than inspections with repairs as needed. The frequency of re-inspection depends on the conditions and ratings given in the initial inspection. When no immediate action is needed but conditions could become critical, a more frequent inspection schedule should be used.
Manual Culvert Inspection
An inspector will preform Manual culvert inspections. Visual inspections of the condition of the embankment, end sections, flow lines, interior culvert, and road are done and recorded by the inspector. The culvert type, shape, length, and size is also recorded. The Inspectors records ratings for the embankments, end sections, flow lines, culvert, and general conditions. The general condition rating will determine the frequency of future inspections. The inspected components are:
Embankment: A raised structure (as of earth or gravel) used especially to hold back water or to carry a roadway. The area between the top of culvert and the pavement.
End Section: A flared attachment provided on either side of the culvert pipe for the purpose of improving hydraulic efficiency and preventing erosion. The headwall, wing walls, and the section of the culvert that is visible without looking inside of it.
Flow Line: A flowline is a line through the center of a channel or a water body, which defines the main direction of flow. The quality of the culvert’s pathway for water to flow towards a ditch, stream, river, etc.
Video Inspection Benefits
A rating system includes detailed descriptions of what each rating means but applying these ratings is still subjective. This issue is impossible to avoid, each inspector has varying opinions of appropriate ratings. The use of video inspection equipment to document field conditions can reconcile these discrepancies. Acquiring live video in the field inspection is an easy way to evaluate and document changes over time. The video inspection process requires a minimal amount of time per culvert while providing a wealth of information. Video inspection is invaluable to identify and document deficiencies such as dips, offset joints, cracks, blockages, infiltration, and more. Accurate assessment of pipeline condition can help prevent faulty installations, predict potential failure points, and identify deficiencies in need of repair. Rovver X is the one system that lets you do everything: control inspections, view and record digital video, log observations, generate reports, and link directly to asset-management software.
Rovver X is the perfect tool for both large and small culvert inspections.