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Vortex and catwalk in RTF (Dec 2007)
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Midland overflow abatement project
See construction photos.
In its efforts to improve water quality in both Onondaga
Lake and Onondaga Creek, Onondaga County is building the Midland
Regional Treatment Facility (RTF) and 2 miles of
conveyance piping.
Between Newell and Tallman streets, combined sewage is
discharged to Onondaga Creek at twenty-one points. These
discharges occur fifty to sixty times per year.
CSOs create human health risks because they add
bacteria, floating trash, organic material, heavy
solids, and grit to city streams and Onondaga Lake. Material
from CSOs collects on vegetation along and in streams.
It looks bad and smells bad, and it can also transmit
disease to humans who may come in contract with the
water. Material from CSOs also depletes the dissolved
oxygen in the water that is necessary for aquatic
life.
Nine of these CSOs will be connected to the Midland
RTF. The remaining twelve are being eliminated through
sewer separation projects.
By implementing this project, Onondaga County will meet or exceed federal and state water
quality
requirements,
reduce human health risks associated with the discharge of
untreated sewage to Onondaga Creek and Onondaga Lake, and eliminate
odors caused by discharging overflows.
The County will also make improvements to the area
affected by construction of the abatement work.
Full information about the project is available in the facility plans:
Facility plan Plan amendment
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Installing the 144-inch pipe near Midland RTF (June 2006)
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All construction work is now complete on the Midland
RTF, and a pre-start up testing period is underway.
The potential for revisions to the Phase III plans is
being evaluated at this time.
Existing collector and trunk sewers in the Midland
service area can store 74% of the average annual wet
weather flow. The piping now under construction will
store another 18%. All of this stored flow will be
conveyed to the Metropolitan Syracuse Wastewater Treatment Plant (Metro) for treatment and
disposal. The RTF will handle the remaining 8% (about
77 million gallons annually).
Swirl concentrators (vortex units) at the RTF will
treat, disinfect, and dechlorinate these 77 million
gallons of flow. With the RTF in place, this treated
wastewater-stormwater will be discharged to Onondaga Creek
only about nine times per year,
Besides the vortex units, the RTF includes a pumping
station, odor control and ventilation equipment,
electrical and control equipment, chemical storage
(liquid sodium hypochlorite and liquid sodium
bisulfite), and a small office. The aboveground
portion of the RTF is 24,000 square feet and 24 feet
high.
The RTF is
not
a sewage treatment plant. Sewage treatment plants
typically operate 24 hours per day everyday and
usually include a biological treatment process. The
RTF will operate
infrequently.
It will fully operate and discharge only when the
storageincluded in the large
diameter conveyance pipes, underground storage tank,
and RTF influent wet wellis exceeded. Even then, a
treated discharge to Onondaga Creek will only occur when the
total
including inherent storage
in the vortex units and disinfection tankis exceeded,
approximately nine times per year.
Onondaga County has been working to reduce combined sewer
overflows in the Midland area for several years:
1969
Ownership of Midland Avenue and Elmhurst combined
trunk sewers transferred from the City of Syracuse to
Onondaga County.
1978
Tallman Street and Bellevue Avenue trunk sewers
transferred from City to County.
Mid-1980s
Onondaga County undertook a series of best management
practices to improve the combined trunk sewer system
and significantly reduced the incidence and volume of
combined sewer overflows. Through the County's
efforts, a number of CSOs were closed, and the volume
of sewer overflows released to Onondaga Creek and Onondaga Lake
was reduced by 90%.
1991
Onondaga County began plans to address and abate remaining
CSOs with a 1991 facilities plan.
1996
Proposed municipal compliance plan (MCP) specified a
CSO abatement project at the Blaine-Oxford streets
site.
1998
The Amended Consent Judgment signed by the County, State, and Atlantic
States Legal Foundation includes a regional treatment
facility with vortex separation at the Blaine-Oxford
streets site for the Midland sewer area. Design and
construction of the project had required milestone
dates for the County to meet.
1998-2000
As part of the planning and environmental review for
the Midland project, Onondaga County re-evaluated potential
locations for the Midland facilities and the
technologies to be employed.
2000
Phase I: A 900-ft conveyance pipeline was installed to
bring the Tallman Street CSO to the RTF site.
Fall 2000
Construction documents for the Midland RTF and related
Phase II conveyances submitted to NYSDEC
Fall 2001
City of Syracuse Common Council voted to refuse to
sell necessary City-owned and -controlled land to the
County for the project.
Nov 2001-Aug 2002
Onondaga County, independently and in cooperation with a
mediation efforts of NYSDEC, identified and evaluated
further alternatives to the proposed RTF.
Aug 2002
Onondaga County adopted a modified project plan reducing the
number of vortex units from four to two and added 2.5
million gallons of underground storagethus increasing
the amount of CSO captured and reducing the amount to
be processed through the RTF and discharged to Onondaga
Creek after treatment.
Oct 2002
Onondaga County sponsors workshop on
disinfection of wastewater with chlorine to
demonstrate the effectiveness and benefits of this
technology. Speakers included USEPA, NYSDEC, and
Syracuse Research Corp.
Nov 2002
U.S. District Court rules that Onondaga County may condemn
property owned by the City that is needed for the Midland
project. Engineers begin preliminary design for the
County's preferred option.
Jan-Feb 2003
Revised and updated facilities
plan submitted to NYSDEC for the Midland Avenue
RTF and conveyances project. Onondaga County Legislature
authorized acquisition of property for construction,
operation, and maintenance of Phase II Midland Avenue
RTF and conveyances.
Mar 2003
Onondaga the County further modified its plan by locating
most of the RTF and the underground disinfection tank
on CENTRO property adjacent to the bus garage.
May-Jun 2003
Federal district court judge supports Onondaga County's
right to use eminent domain with just compensation to
acquire a City-owned property. City files appeal.
County proceeds to purchase needed private properties
and assists property owners in finding new homes and
provides compensation for moving.
Jun 2003
Amended facility plan and
revised engineering design report forwarded to NYSDEC
for review.
Nov 2003
NYSDEC approves updated facilities plan and engineering design report.
Feb 2004
Contract for building demolition put out for bid.
Bids advertised for construction of Phase II Midland
RTF and conveyances.
May 2004
Demolition contract awarded. Site demolition begins.
Aug 2004
Notices-to-proceed issued to general contractor and
electrical contractor. Demolition of structures on
the construction site completed. Under agreement with
the Syracuse Housing Authority, public housing
residents located in the Blaine-Oxford area are
assisted in finding new apartments. Relocations are to
be completed by November 15, 2004.
Sep 2004
Construction begins with site preparation work.
Perimeter fencing is installed, office trailers
arrive on site, and the former apartment building at
115 Oxford Street is demolished. In all, seven
structures are demolished, including five houses,
purchased from their owners, an abandoned garage, and
one apartment building.
Oct 2004
Oxford Street bridge is demolished. Work begins to
relocate utility lines before relocating Main
Interceptor Sewer which crosses the construction site.
County officials meet with area residents at a meeting
of SUN-Tallman Action Council. Questions are asked
and responded to regarding construction and the
proposed schedule of construction activities.
Test wells are installed for dewatering.
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Installing steel sheeting in preparation for replacing a setment of the 48-inch main interceptor sewer (MIS) with new 54-inch HDPE piping (Nov 2004)
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Mar 2005
One segment of MIS on the Midland construction site
replaced. Excavation begins for disinfection tank.
Jun 2005
Completed replacement of the 48-inch brick-and-concrete
MIS segment across the Midland construction
site with 54-inch high-density polyethylene plastic
pipe.
Jun 2006
Conveyance line to Bellevue Regulator crosses Onondaga
Creek.
Aug 2006
Onondaga County Legislature authorizes issuance of an
additional $49,890,420 in bonds to pay increased
cost of improvements for Midland facility. The
Legislature also authorizes $218,100 for
acquisition of real property for the construction,
operation, and maintenance of the Midland project.
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Along the route of the 144-inch conveyenceunder construction, Nov 06
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Sep 2006
Bellevue Avenue conveyance creek crossing is complete.
Jan 2007
Final design documents on Midland Phase III completed
and submitted to DEC for review and approval.
Apr 2007
Installation of the Phase II portion of the 144-inch
pipe is completed. The length of the pipeline is 1200
feet in this section. Midland Phase III is advertised
for bid.
Jul 2007
Midland Avenue reopens to traffic.
Aug 2007
Bids advertised for building demolition contract for
Midland Phase III (and Harbor Brook RTF). Six
structures will be demolished for Midland Phase III
conveyance. (Contract is let in Dec 2007.)
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Installing the last section of roofing on the Midland RTF (Aug 2007)
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Oct 2007
Concrete pours complete at 20,546 cubic yards.
Jan 2008
Construction completed on RTF
Jan 2009
Expected completion of construction of the Phase III
pipeline.
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