Atlanta and its surrounding counties have been growing at an incredible rate
for many years. The impact of the constant influx of people, construction of
new homes and commercial development has increased the stress on the infrastructures
that support everyday life. The increase in traffic is one of the most visible
aspects of this growth and development. One of the least visible aspects is
the aging underground infrastructure that carries sewage to our treatment facilities.
That is, it’s least visible until sewage backs up into backyards and
basements or flows into our creeks.
A new 10-million gallon linear storage facility, in conjunction with the existing
34-million gallon Intrenchment Creek CSO Storage Tunnel, will be constructed
to increase the total storage capacity to 44 million gallons. To construct
the new storage facility, the chosen site must first be cleared. A 30-foot
diameter vertical construction access shaft, approximately 120 feet deep, will
be excavated into rock and its walls will be reinforced with concrete where
required for stability. This shaft will provide access to construct the below-ground
storage facility that will be excavated into solid rock.
In addition, the existing East Area CSO treatment facility will be upgraded to
treat the CSO’s to a higher level. Currently the flows pumped from the
tunnel are treated using bar screens, grit removal, settling basins and chlorine
disinfection. The upgrade to the facility will include the addition of fine screening,
filters and enhanced disinfection systems to control harmful bacteria and other
residuals. The cleaned CSO flows into Intrenchment Creek, which is tributary
to the South River.
The linear storage facility supplements the existing storage capacity to
increase the annual volume of CSO captured as required to comply with new
water quality standards. The upgraded treatment facility (a separate project)
will treat the CSO’s to a level that surpasses current screening and