This surveillance programme for Aphanomyces astaci uses environmental DNA (eDNA) monitoring for detection of A. astaci spores directly from water filtrates. The presence/absence of eDNA from noble crayfish (Astacus astacus) and signal crayfish (Pacifastacus leniusculus) is also determined to evaluate the habitat status. Detection of noble crayfish eDNA, combined with the absence of eDNA from A. astaci and signal crayfish, support the presence of non-infected noble crayfish which constitutes the desired habitat status. In 2024 eDNA from A. astaci was detected within the restriction zone in Lake Rødnessjøen in the Halden watercourse, and within the restriction zone in River Hæra. The active outbreak of crayfish plague in River Hæra spread upstream into River Dalselva during the summer, but remained within the restriction zone. Illegally introduced signal crayfish was discovered in Lake Øyern, a large lake in the Glomma watercourse, after notification from the locals. Tissue samples from the signal crayfish was analysed and confirmed A. astaci positive. Frequent detections of noble crayfish eDNA within the regulated A. astaci restriction zones of the Halden watercourse, Mosse watercourse, and the rivers Vrangselva and Finnsrudelva in Eidskog, suggest the presence of vital noble crayfish populations within A. astaci restriction zones.