Engineers present model, recommend stepped flushing, targeted cleaning and selective replacements to tackle Waldwick's rusty-water complaints

Consulting engineers presented a calibrated hydraulic model of Waldwick's water distribution and a stepped plan to reduce chronic discoloration and aesthetic complaints.

The consultants said they spent about 18 months compiling operator data, mapping complaints and building a 3-D model to replicate the borough's flow patterns. They said aging metallic mains and changes in how sources are operated have altered flow paths, producing localized pockets of low velocity where corrosion and sediment accumulate.

"Almost all infrastructure of this kind is composed of materials that tend to age and degrade over time," the lead presenter said, explaining the model's purpose: to forecast how operational changes or repairs would affect downstream water quality before the borough spends capital.

The team recommended a tiered approach. First, expand the existing hydrant-flushing program in frequency and intensity and continue it as an operational practice; consultants stressed flushing should avoid freezing conditions and summer peak demand. Second, where complaints persist, use intensified or unidirectional flushing to induce scouring velocities in targeted lengths of pipe. Third, if flushing results and follow-up samples indicate persistent turbidity or tuberculation, perform selective test pitting and pipe couponing to measure wall…