title: Comparison of the inspector and rating protocol uncertainty influence in the condition rating of sewers.
abstract: Wastewater drainage systems asset management decisions, in particular regarding rehabilitation interventions, are largely dependent on close-circuit television (CCTV) inspection results. However, the results of CCTV inspections are affected by several sources of uncertainty. Within the present communication, the inspector's uncertainty is quantified by comparing periodic inspection reports from three trunk sewers of a Portuguese sewer system. The inspections were carried out by the same experienced inspector using the same equipment. Therefore, the uncertainties from the lack of experience and the difference of the inspector and equipment were ruled out. The protocol uncertainty is also quantified comparing the results obtained with the Water Research Center (WRc) and the National Research Council of Canada (NRC) protocols condition ratings. Both operational and structural condition rating were analysed, but emphasis was given to the later since it dictates the repair and replacement interventions.
authors.affiliation: Department of Civil Engineering, Architecture and GeoResources, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1049-001 Lisbon, Portugal E-mail: vitor.sousa@ist.utl.pt.
authors.forename: V
authors.initials: V
authors.lastname: Sousa
authors.affiliation: Department of Civil Engineering, Architecture and GeoResources, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1049-001 Lisbon, Portugal E-mail: vitor.sousa@ist.utl.pt.
authors.forename: F M
authors.initials: FM
authors.lastname: Ferreira
authors.affiliation: Department of Civil Engineering, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal.
authors.forename: I
authors.initials: I
authors.lastname: Meireles
authors.affiliation: Department of Civil Engineering, Architecture and GeoResources, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1049-001 Lisbon, Portugal E-mail: vitor.sousa@ist.utl.pt.
authors.forename: N
authors.initials: N
authors.lastname: Almeida
authors.affiliation: Department of Civil Engineering, Architecture and GeoResources, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1049-001 Lisbon, Portugal E-mail: vitor.sousa@ist.utl.pt.
authors.forename: J
authors.initials: J
authors.lastname: Saldanha Matos
mesh_terms: D004323:Drainage, Sanitary / Q000592:standards*; D004784:Environmental Monitoring; D005160:Facility Design and Construction; D012722:Sewage; D014865:Waste Disposal, Fluid; D014872:Water Movements
chemical_list: D012722:Sewage