Water scarcity water reuse and environmental concerns present challenges for cooling water systems. Operating cooling water systems at cycles of concentration (COC) increases potential deposition on heat exchangers tower film fill and piping. This necessitates robust treatment programs to prevent deposition (both fouling and scaling) and corrosion.This paper will present approaches to manage cooling systems operating under high stressed conditions attributable to make up water contaminants (e.g. high phosphate aluminum and iron). Technologies for preventing deposition in cooling systems operating under stressed conditions will be discussed.Keywords: Deposit control phosphate scaling corrosion control polymer technologies suspended solids high cycle stressed cooling systems.