Build Over Drainage Survey in Penkridge
Pre-construction build over drainage survey carried out at a residential property in Penkridge, Staffordshire, ahead of proposed development works.
The survey assessed the condition, operational performance and structural integrity of both the shared and private drainage systems within the proposed construction area, helping identify any defects that should be addressed before groundwork and foundation works begin.
Location: Penkridge, Staffordshire
Service: Build over drain survey
Overview
We were instructed to carry out a build over drainage survey in Penkridge ahead of proposed construction works at a residential property. The purpose of the survey was to establish the condition of the drainage infrastructure within the development area and determine whether the existing pipework was suitable to remain in service during and after construction.
The inspection identified both a shared drainage line and private drainage pipework serving the property. At the time of the survey, the accessible drainage infrastructure was operational and wastewater was flowing freely through the system. No significant restrictions, active blockages or loss of service were identified.
However, the CCTV survey also highlighted evidence of structural movement within sections of the private drainage network that needed to be considered before construction began.
What we did
We carried out a pre-construction CCTV drainage survey across the accessible drainage infrastructure within the proposed development area. The survey was undertaken to:
Identify shared and private drainage assets
Assess the condition of the existing pipework
Confirm that the drainage system was operational
Identify structural defects that could be affected by construction
Assess whether the drainage infrastructure was suitable for continued use
Provide recommendations for remedial works before excavation and groundworks
Establish a baseline condition before construction begins
Both the shared and private drainage systems were inspected and graded based on their condition and serviceability.
Outcome
The survey confirmed that both the shared and private drainage systems were functioning correctly and remained serviceable at the time of inspection. The shared drainage line was considered suitable to remain in use in its existing condition, with routine monitoring and appropriate protection recommended throughout the construction works.
Within the private drainage network, however, the CCTV inspection identified several medium displaced joints caused by structural movement. Although these defects were not currently preventing the system from operating, displaced joints can create internal irregularities that retain solids, reduce the effective bore and increase the likelihood of future blockages.
There was also a risk that the existing movement could worsen if the pipework was subjected to additional loading, vibration or ground disturbance during excavation, foundation installation or other construction activities. For this reason, we recommended completing remedial works before significant groundworks commenced. The preferred repair method was the installation of internal structural patch liners across the affected joints.
Overall, both drainage systems were classified as Grade B – Serviceable, but repairing the displaced joints before construction would help protect the private drainage infrastructure and reduce the risk of drainage failure once the development was complete.
This project is a strong example of why build over drainage surveys are valuable before construction begins. A drainage system can appear to be functioning perfectly well while still containing structural defects that may become more significant once excavation, loading and ground disturbance take place.
Location
This project was carried out at a residential property in Penkridge, Staffordshire, ahead of proposed construction works affecting shared and private drainage infrastructure.
We regularly undertake build over CCTV drainage surveys and pre-construction drainage inspections across Penkridge, Stafford, Cannock, Wolverhampton, Stoke-on-Trent and the wider Staffordshire area, helping homeowners, architects and contractors assess drainage condition, identify defects and support water authority approval before building works begin.