Background
The replacement of the Network Rail bridge at Three Colts Lane took place in a dense urban environment, surrounded by residential properties at Bahram Court and mixed-use commercial units.
The project required major bridge removal, piling, cable diversion and steel installation to be undertaken both within core hours and during railway possessions and blockades, including over the Christmas 2022 period.
The challenge was to gain statutory consent for these noisy, time-critical works while maintaining community confidence and legal compliance under the Control of Pollution Act 1974.
What We Did
Section 61 Applications and Consents
We prepared comprehensive Section 61 applications for both the main bridge site and the remote compound. Each application incorporated:
- Predicted noise levels following BS 5228-1:2014 and vibration screening to BS 5228-2:2014;
- Identification of sensitive receptors and predicted sound exposure contours;
- BPM commitments specific to the bridge replacement and compound activities;
- Defined monitoring and reporting protocols for LBTH compliance checks.
Out-of-Hours Dispensation
Because key activities could only take place during railway possessions and night blockades, we prepared an Out-of-Hours (OOH) Dispensation Application, covering:
- Weekend and overnight possessions between November 2022 and February 2023;
- Activities such as trial holes, Haki staircase installation, HV cable diversions, track reinstatement and bridge lift;
- Updated predicted noise levels, BPM measures, and public notification procedures
The dispensation was approved, allowing the project to progress under continuous acoustic assurance.
Best Practicable Means (BPM)
To ensure compliance and minimise disturbance, we developed a site-specific BPM framework, agreed with Murphy and LBTH environmental officers.
Key controls included:
- Super-silent plant and acoustic shrouding for compressors and generators;
- Temporary noise barriers along Three Colts Lane and Bahram Court façade line;
- Early evening sequencing of the highest-impact works before night periods;
- Plant-on-time limits and mandatory engine shut-offs during idle periods;
- Team briefings on noise etiquette — e.g., use of radios instead of shouting, and restricting loading activity to pre-approved times;
- Community liaison: pre-works letters to residents within 200 m radius, dedicated helpdesk for enquiries, and rapid response to any complaints;
- Real-time noise monitoring to flag exceedances and confirm control effectiveness.
These BPM controls were formally referenced within the S.61 documentation and monitored throughout the works.
Noise and Vibration Monitoring
A network of Class 1 sound level meters was deployed at Bahram Court and near the compound boundary, logging LAeq, LAFmax, and vibration PPV during all possession periods.
Data were reviewed daily and compared with the predicted levels in the approved consents. Monitoring confirmed that all events remained within allowable thresholds, with no reportable exceedances or resident complaints throughout the works.
Project Progress
The works were completed safely and on programme during the February 2023 blockade. By combining detailed modelling, clear communication, and site-specific BPM controls, we enabled noisy rail possessions to proceed quietly, safely, and compliantly within one of London’s most constrained residential areas.
