Baltimore County Manhole Inspection Program

Baltimore, MD

PEER was contracted to assist in the inspection of manholes in Baltimore County. What began as a two-month pilot study to determine the cost effectiveness of contracting out manhole inspection work, has grown into a multi-year manhole inspection project.  PEER has provided experienced manhole inspectors and equipment to perform the work.

The Baltimore County, Maryland, Department of Public Works, Bureau of Utilities (County) has entered into a Consent Decree to ensure compliance with the Federal Clean Water Act and Maryland water pollution control laws. The team was hired to manage the overall consent decree program, as well as to perform the Sewershed Evaluation Study in the Upper Jones Falls Sewershed. Among other activities, the consent decree requires the inspection of all manholes and other sewer system structures according to a specified schedule with significant penalties per manhole for every day that the team does not meet the deadline.  In prior years, County personnel has performed the work required in the County manhole inspection program.  The team, however, has determined that current County resources are insufficient to meet the deadline specified in the Consent Decree and thus has hired PEER to complete the task.

Each inspection consists of a site survey upon arrival to verify location data and to assess the ground conditions around the structure, ensuring that any problems found are noted. Once the cover condition is assessed and documented, it is removed and the internal structural and operational inspection is conducted. Defects including, but not limited to, evidence of inflow and infiltration, missing bricks and restrictions of the flow in the channel are documented, as are the conditions of all pipe connections. Invert and pipe diameter measurements are taken to complete the inspection. All of the data is gathered using an Envirosight Quickview pole camera to capture still photos and it is then linked to a computer-based database system. Using this system, a complete manhole inspection can be completed without requiring a manned confined space entry.

Using this remote inspection methodology, more manholes can be inspected per day and Consent Decree deadlines can be met, without incurring high penalties.