Publication

Minimization of sewage network overflow

Journal Article (2014)

Journal

Water Resources Management

Pages

41-63

Volume

28

Number

1

Doc link

http://dx.doi.org/10.1007/s11269-013-0468-z

File

Download the digital copy of the doc pdf document

Abstract

We are interested in the optimal control of sewage networks. It is of high public interest to minimize the overflow of sewage onto the streets and to the natural environment that may occur during periods of high rain. The assumption of linear flow in a discrete time setting has proven to be adequate for the practical control of larger systems. However, the possibility of overflow introduces a nonlinear and nondiferentiable element to the formulation, by means of a maximum of linear terms. This particular challenge can be addressed by smoothing methods that result in a nonlinear program (NLP) or by logical constraints that result in a mixed integer linear program (MILP). We discuss both approaches and present a novel tailored branch-and-bound algorithm that outperforms competing methods from the literature for a set of realistic rain scenarios.

Categories

control theory, dynamic programming, nonlinear programming, optimal control, optimisation.

Author keywords

sewer network, optimal contol, MLD, nonlinear programming problems

Scientific reference

B. Joseph, M.N. Jung, C. Ocampo-Martínez, S. Sager and G. Cembrano. Minimization of sewage network overflow. Water Resources Management, 28(1): 41-63, 2014.