Bridge Scour Monitoring

In remote areas, may structure are at risk from erosion due excessive flows of water. Rainfall radar has limited accuracy in mountains and hence other solutions are required to report the levels or water flowing under structure like bridges to enable structural engineers ascertain risks to structural integrity created by the passage of water. Without knowing the level of flows, practice is to halt services for safety in the presence of any significant suspected rainfall until a structural engineering team has visited each site, despite the fact that in the majority of cases the river height is minimal.

By combining three of RDN’s BDT micropower water level sensors, a VEGA level radar, an Iridium Satellite SBD modem and one of RDNs versatile logic controllers Radio Data Networks have created a cost effective Bridge Scour Monitor that can be installed absolutely anywhere on the planet, including parts of the Scottish Highlands, devoid of power, cellular coverage and other means of communications.

The first of its kind anywhere in the World, and the first deployment of an Iridium system on the UK Rail Network, RDN’s Bridge Scour Monitor is a lightweight easy to transport system weighing less than 10% of NW Rail’s previous data-logger battery system. Furthermore, it can into a rucksack, including the battery. Yet it delivers real-time data and is capable of up to 5-years operation on a battery pack or with solar an indefinite period in service.

Ordinarily when the river level is benign , the river level is measure and reported twice daily as in order to verify the function of the system. There are three BDT sensors are suspended above the river at set points called Green, Yellow and Red. When the level reaches the Green level the a reading is instantly taken and the reporting accelerates to hourly, on reaching the the yellow, half hourly and on red every 15-minutes.

What makes the system so special is the high level of SIL offered by the BDTs. Unlike pressure transducers or conductivity sensors, which when out of the water do not produce a reading, the BDT being a dielectric sensor actually generates a reading proportionally to the atmosphere and and hence tracks weather when in air and produces an alert when in water, providing a unique string of health messages which enable verification and cross-correlation from afar.

This solution is one of the many that come out of Radio Data Networks stables at its Innovation Farm HQ every year. It can be easily used on highways, canals, rivers and as a flood monitoring system and as proven by NW Rail’s own trials with RDNs track flood monitoring at RIDIC their UK research centre