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Preliminary Treatment

Grit

Grit and sand originate from upstream collection system pipe separations or breaks.

Grit and sand can enter a collection system where manholes are located within a

flood or tidal plain, resulting in sediments washing into the collection system.

Grit and sand cause significant impacts throughout the facility. Grit and sand if not

removed, wear out internal pump parts, clogs pipes and settles in tanks, consuming

valuable capacity and causing hydraulic short circuiting and less than optimum

treatment.

The amount of grit removed weekly is dependent on the age of the upstream

collection system, the amount of collection system construction underway. Even the

soil substrate that can have greater impact to a treatment in sandy areas.