Enhancing hydraulic data reliability in sewers

Abstract

Recently, water utilities have been making considerable investments in sewers' monitoring; however, in most cases, assuring data reliability is yet a challenge. Often, hydraulic data is collected in sewers overlooking best practice aspects. Assuming confidence in data, while disregarding cautions verifications, might lead to inadequate uses of data. The paper presents a methodology aiming to narrow the gap between science and industry, regarding monitoring programs in urban drainage. A procedure to enhance hydraulic data reliability, in line with ISO/IEC 17025:2017, was developed, applied and validated, enabling a final evaluation on data and site adequacy and an overall identification of improvement opportunities. The availability of a valuable case study comprising 32 flowmeters from Portuguese utilities, in eastern Europe, presented an opportunity to create a story line, test the procedure's coherence, present it to the technical community and evaluate the constraints that utilities, in their everyday working context, are faced with. The procedure is presented in detail and a collection of examples of its application is shown. In the final evaluation, most monitoring stations' alignment with best practice requirements were either high (25%) or acceptable (44%), regarding their overall performance and compliance with both data and site adequacy. For all of them, improvement opportunities were identified.