  The identification of pipe roughnesses in a water distribution network is
formulated as nonlinear system of algebraic equations which turns out to be
demanding to solve under real-world circumstances. This paper proposes an
enhanced technique to numerically solve this identification problem, extending
the conventional Newton-Raphson approach with second-order derivatives in the
determination of the search direction. Enabled through some interesting
mathematical findings, the resulting formulation can be represented compactly
and thus facilitates the development of an efficient and more robust
solving-technique. Algorithms on the basis of this more enhanced solving method
are then compared to a customized Newton-Raphson approach in simulation
examples.
