Gastrointestinal parasites threaten public health where sewage is improperly managed. Untreated sewage in the environment increases the risk of disease transmission. This study investigated gastrointestinal parasites in effluents from broken sewers and assessed the Knowledge, Attitudes, and Practices (KAP) of the local population in Nsukka, Enugu State, Nigeria. A total of 463 effluent samples were collected and analysed using zinc sulphate (ZnSO₄) flotation and formol-ether concentration techniques. Structured questionnaires were administered to 367 residents to assess KAP regarding gastrointestinal parasites. Overall parasite prevalence was 28.10% and 9.70% using formol-ether and ZnSO₄, respectively. With formol-ether technique, prevalence varied considerably across sites (χ² = 37.54, p=0.04). Nsukka town had the highest number of species (6). The prevalence of Strongyloides stercoralis was highest, especially in Ibagwa-Aka. Helminths (17.50%) were more common than Protozoa (9.30%). The highest parasite occurrence was in June (31.2%) and July (15.90%), and 56.4% of the respondents considered sewage a source of infection. Open defecation (28.60%) and use of untreated water (46.00%) were prevalent risky behaviours. Burst sewers are reservoirs and pathways for the spread of gastrointestinal parasites. Therefore, proper maintenance of sewers and community health education are necessary to prevent public health risk.