Where have All the Aboiteaux Gone? Mapping Burried Historic Drainage Systems in New Brunswick, Canada

The provincial government of New Brunswick Canada has undertaken the task of rehabilitating historic agricultural marsh lands along the shores of the Petitcodiac River. Since this proposed undertaking will negatively impact shoreline indigenous soils, provincial regulations triggered an archaeological resources assessment. One component of the archaeological program conducted by AMEC was an EM31-SH survey of the proposed shoreline impact areas. Spatial reference was recorded using a Trimble AG114 Global Positioning System (GPS). The principal archaeological objective of the EM31-SH survey was to identify potential subsurface prehistoric and historic archaeological resources. Historically, since the 17th century, the shoreline marshes of the Petitcodiac River have been utilized for agricultural purposes; using a system of dykes (berms) and aboiteaux (drainage structures including oneway valves) that allow water to drain from the marsh while preventing river tidal waters from flooding the marsh. The construction of dykes and aboiteaux in the 1950s “eliminated” any preexisting historcal structures. Thus, while there remains physical remnants of the mid-19th century drainage system, there is little surficial evidence of the preexisting historical systems, Identifying the locations of the both potential prehistoric and historic archaeological features using traditional archaeological testing methods would have been both expensive and time consuming given the large area.