New Mapping Extends Known Length of Dorchester Roman Aqueduct

Archaeologists have determined that one of the nation’s most extensively studied aqueducts is, in fact, longer than initially believed. A team from Bournemouth University (BU) has announced that they have “conclusively mapped” the source of the Dorchester aqueduct for the first time. Constructed nearly 2,000 years ago, the aqueduct played a crucial role in Roman life within the Dorset town, providing water for its public baths, fountains, and affluent residences. The BU team has now established that its length is just over a mile (2kms) greater than first estimated. Harry Manley, from BU’s department of life & environmental sciences, remarked: “This aqueduct has been investigated by archaeologists for over a century.“Despite extensive examinations in the 1990’s, the source of its water and the upper sections of its course have never been conclusively mapped, until now.” Previous studies had indicated that the aqueduct’s source, which followed a winding 12.4 mile (20km) path up the Frome valley northwest of Dorchester, was a lake in Steppes Bottom. However, the BU team’s efforts have revealed that its route actually extended further upstream to the village of Notton on the river Frome. Mr. Manley commenced his research by analyzing publicly available lidar data, a method that generates 3D terrain maps using a laser emitted from an aircraft. This data allowed him to trace the elevation and physical characteristics of the land upstream of Steppes Bottom. He then compared this information to a survey conducted by the university during an earlier study at Frampton Villa, situated further along the newly identified route, near Nunnery Mead. He stated: “The geophysical survey revealed signs of a narrow channel running northwest to southeast. This matched up with my findings from the lidar data, so it seemed like the smoking gun that proved the aqueduct ran through the area.” To confirm the waterway’s presence, the BU team conducted a ground-penetrating radar survey and subsequently performed a small excavation, during which they uncovered evidence of the aqueduct channel. “For the citizens of Dorchester to have this aqueduct constantly providing them with fresh water would have been a matter of civic pride,” Mr. Manley commented.”Understanding more about how it was constructed and maintained, and where it began, adds further detail to this vital aspect of Roman life.”