A magnetometry survey was conducted to inform proposed groundworks at two sites for the Louth Flood Alleviation Scheme. Magnetic anomalies of extensive modern disturbance and services, traces of natural palaeochannels and geological variation were recorded at the northern site, along with the remains of a linear feature, thought to represent the remains of a bank associated with a former rifle range. Anomalies thought to represent the remains of two possible prehistoric ring ditch features were also recorded at the southern site. {1}{2}