In recent years, we have used UAVs to inspect and photograph a wide range of ancient monuments and heritage buildings – everything from Stonehenge to castles and stately homes. However, one of the services we are most often called upon to deliver involves wall-top inspections.
Many castles and similar structures have lost their roofs over the years, so the tops of walls are left exposed and unprotected. Frost damage and the growth of plants (and even small trees) can then cause damage to the upper parts of the remaining walls. This poses a problem for those responsible for their maintenance, because they are often very difficult to access and inspect.
United Utilities recently contacted us with a request for an aerial survey of a 250m elevated pipeline that serves a wastewater treatment plant in Stockport. It wanted to use the results of this inspection to determine repair and maintenance plans.
Pipe bridges and elevated sewers are often inspected manually, but this typically entails the use of scaffolding, which is slow to erect and therefore expensive. A UAV-based inspection offered an opportunity to make significant time and cost savings. In this case, overhead powerlines presented an additional hazard and this lent further weight to the argument in favour of using a drone rather than metal scaffolding.
Silchester in Hampshire may not be as well known as some other Romano-British settlements, but it is nevertheless a site of considerable interest to heritage specialists.
The city began in the 1st century BC as Calleva, the pre-Roman homeland of the Atrebates tribe. After the Roman conquest in 43 AD, it grew rapidly and was renamed Calleva Atrebatum. It was abandoned in the 6th or 7th century but, unusually, it was not reoccupied in the medieval period. As a result, no further construction took place and its remains have lain largely undisturbed. Many of the perimeter walls survive, as do parts of the city amphitheatre. In fact, it stands as one of the best preserved Roman towns in Britain. Continue reading “Heritage Survey: the Roman City of Silchester”
We are seeing growing demand for building surveys, roof inspection projects and associated 3D modelling work. A recent project in Lancaster illustrates the services we are increasingly being asked to provide.
Set close to the town centre, Cable Street is a stone-built property comprising 3, 4 and 5-bed student flats. Designed by Richard Gillow in 1759, the building has considerable heritage value, though it has been repeatedly modernised and upgraded to maximise its appeal to the student market. Continue reading “Roof Inspection: 3D Modelling, Lancaster”
Mott McDonald Bentley, Wessex Archaeology and the Environment Agency
In recent months, we’ve made a number of visits to York, where we’ve been conducting an extensive aerial survey of land adjacent to the River Ouse.
Following torrential rain and subsequent flooding in December 2015, the Environment Agency took the decision to review and improve flood defences involving the Foss Barrier. The barrier features a gate that can be closed to prevent rising waters in the Ouse from backing up into the River Foss and flooding parts of the city. However, in 2015, these measures had proven inadequate. Having devised an improvement plan, the Agency appointed Mott McDonald Bentley to deliver the necessary upgrades, which include fitting eight new, high capacity pumps and associated control systems. Continue reading “Topographic Survey: River Ouse, York”
Topographic surveys are widely used across the civil engineering and construction industries – on sites where it’s important to get a clear understanding of shape and contour. However, the traditional approach – using teams of surveyors to locate hundreds or thousands of points on a chart – presents a number of challenges that modern UAVs can address. Continue reading “Topographic Surveys Using UAV:”