Water Treatment Process

 

Water Treatment Plant

The City of New Bern Water Treatment Plant began operation in May 2010.  This system consist of a filter/softener treatment plant, a two million gallon ground storage tank, and 15 wells which draw water from the Castle Hayne Aquifer.  The Castle Hayne Aquifer is much larger and more easily replenished than the Black Creek Aquifer, but its water is of considerably lower quality.  Raw water pumped from the wells contains metals (iron and manganese), hydrogen sulfide (odor), and high levels of calcium and magnesium (hardness).

 

Water Treatment Plant Process

The treatment process begins with aeration, which causes the metals to begin oxidizing (rusting) naturally.  Aeration also removes most of the hydrogen sulfide in the water. After some detention time, an oxidizing chemical is added to ensure that oxidation is complete before filtering.  Any metals not fully oxidized will simply pass through the filters.  The filters also remove any remaining hydrogen sulfide.

Water is then softened to remove calcuim and mangesium.  The softeners remove all hardness, so it is necessary to bypass a fraction of the water in order to reach the desired hardness level.  Softening is by far the most expensive aspect of this treatment system.  The salt used to regenerate the softeners accounts for a third of the Water Treatment Plant's operational costs, including electricity.  Extrememly soft water also has a corrosive effect in the distribution system, resulting in increased wear and maintenance of pumps, valves, and metallic pipe/fittings.  Our finished water hardness level is the result of research, testing and consultation with surrounding systems utilizing similar source water and treatment techniques. 

Chlorine is now added for disinfection as the water is being pumped to the ground storage tank.  Orthophosphate, a corrosion inhibitior, is also added to further prevent the finished water from reacting with metallic parts (i.e. iron, lead, copper) for the City's distribution and home plumbing systems.  Waters from the Cove City storage tank and the Water Treatment Plant storage tank are blended before entering the distribution system.

The City of New Bern's distribution system consists of a four million gallon ground storage tank, five elevated storage tanks, and three booster pump stations.  A sixth elevated tank and two additional booster pump stations are currently under construction in preparation to meet future demand.

2012 Water Quality Report

 


City of New Bern
PO Box 1129
New Bern, NC 28563-1129
Engineering Main # (252) 639-7526
City Phone Directory