Modelling both the continual erosion and regeneration of discolouration material in drinking water distribution systems

• Published in: Water science & technology. Water supply 2014-01, Vol.14 (1), p.81-90
• Main Authors: FURNASS, W. R, COLLINS, R. P, HUSBAND, P. S, SHARPE, R. L, MOUNCE, S. R, BOXALL, J. B
• Format: Article
• Language: English
• Subjects: Applied sciences; Buildings. Public works; Coding; Computation methods. Tables. Charts; Computer simulation; Discoloration; Distribution; Distribution. Storage; Drinking water; Erosion; Exact sciences and technology; Formulations; Laboratories; Mass transport; Mathematical models; Modelling; Particulate matter; Regeneration; Regeneration (biological); Sensitivity analysis; Structural analysis. Stresses; Suspended particulate matter; Systems analysis; Water distribution; Water distribution systems; Water engineering; Water management; Water supply. Pipings. Water treatment
• ISSN: 1606-9749; 1607-0798
• DOI: 10.2166/ws.2013.176

The erosion of the cohesive layers of particulate matter that causes discolouration in water distribution system mains has previously been modelled using the Prediction of Discolouration in Distribution Systems (PODDS) model. When first proposed, PODDS featured an unvalidated means by which material regeneration on pipe walls could be simulated. Field and laboratory studies of material regeneration have yielded data that suggest that the PODDS formulations incorrectly model these processes. A new model is proposed to overcome this shortcoming. It tracks the relative amount of discolouration material that is bound to the pipe wall over time at each of a number of shear strengths. The model formulations and a mass transport model have been encoded as software, which has been used to verify the model's constructs and undertake sensitivity analyses. The new formulations for regeneration are conceptually consistent with field and laboratory observed data and have potential value in the proactive management of water distribution systems, such as evaluating change in discolouration risk and planning timely interventions.