Contamination of Pacific oysters, Crassostrea gigas, by human norovirus (HuNoV ) is a major constraint to sustainable shellfish farming in coastal waters of the Northeast Pacific. HuNoV is not a marine virus and must originate from a human source. A barrier to effective management is a paucity of data regarding HuNoV dispersal in the marine environment. The main objective of this study was to identify the spatial distribution and persistence of HuNoV in an active shellfish farming region in the Northeast Pacific. Market-size C. gigas were sequentially deployed for two-week intervals at 12 sites during the 2020 winter risk period from January to April . HuNoV quantification was performed by reverse transcription real-time PCR (RTqPCR ) according to method ISO 15216-1:2017, with minor modifications. The estimated prevalence of genotypes GI and GII HuNoV associated with human illness in oyster digestive tissue was 0 ± 0 and 0.8 ± 0.3 %, respectively. Spatiotemporal analysis performed using the Bernouilli model available in SaTScan v9.6.1 revealed contamination of oysters with GII HuNoV changed through time and space during the surveillance period. The largest GII HuNoV cluster had a radius of 8.4 km and the longest duration of a cluster was ≤ 6 weeks. These results will help mitigate HuNoV illnesses by informing the shellfish industry and regulators on the size and duration of harvest closures following HuNoV outbreaks.