Monitoring environmental impact: not a catch-all solution

The replacement of the sewage system and the construction of a drainage system may possibly affect the existing buildings in the Emmakwartier. Reason for Stadswerk072 (municipality of Alkmaar) to have architectural surveys carried out prior to the works and to monitor the environmental impact during the works. Known territory for Fides Expertise. Literally and figuratively.

Fides Expertise is regularly called in by the Municipality of Alkmaar to measure the environmental impact of infrastructure works. The Emmakwartier is also not unfamiliar territory for the experts. "At an earlier stage, we did architectural surveys here for grid operator Liander," says Fred Pannekoek of Fides Expertise. "However, that is separate from this project, because prior to Schot Infra's work we carried out another architectural survey in accordance with the BRL 5024 at all properties in the district. In this case commissioned by the municipality itself." According to Pannekoek, a smart move. This avoids liability for possible damages not caused by the municipality. "By not considering the structural surveys and monitoring as a closing item, you can keep a grip on the quality of the monitoring in a large project like this and intervene in time if necessary." 

Fides Expertise installs vibration meters and performs deformation measurements at the site where the contractor is currently working.

Deliberate choice of most vulnerable properties
"We stand for quality," Pannekoek continued. "You have to do a structural survey and environmental monitoring well or else not. We used the contractor's schedule to do the structural recording shortly before the work began. We also installed vibration meters and performed deformation measurements at the site where the contractor was working at the time. Providing every building with a vibration meter is not doable, which is why we always choose the most vulnerable buildings per section, that is, a building in lesser condition or with few building layers (lower own weight)." According to Pannekoek, several damages were reported during the work. "We processed these to assess whether what is being claimed was a result of the work. In a limited number of cases, we had to award the minor cosmetic damage because it was plausible that it was caused by the work. In most cases, we were able to determine from the preliminary survey that it was an old defect."

Fides Expertise always works in accordance with the latest technology and on the basis of calibrated process certificates, such as the BRL 5023 for measuring vibrations and the BRL 5024 for performing building surveys. Fides' experts are collaborating on the extension of BRL 5023 regarding the measurement of environmental effects caused by construction and demolition activities. "In addition, for vibration monitoring we apply the SBR guidelines SBR-A damage to buildings and SBR-B nuisance to persons where we even actively participated in the revision of the 2017 SBR guidelines. So we know exactly what we are talking about and clients can therefore rely on an expert opinion," Pannekoek concludes.