Facts about wastewater projects

4 Pages·1997·0.48 MB·English

by  Massachusetts Water Resources Authority

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" UMASS/AMHERST
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Facts about OCT t
University of Massachusetts
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Wastewater
A Massachusetts Water Resources A ut h RiiJLP b n a iiik^iijim, 1997
""W" n 1986 the Massachusetts Water Resources Critical aspects ofthe operating program
include an aggressive industrial pretreatment/
g Authority (MWRA) began an ambitious pollution-prevention program designed to remove
program to upgrade its regional sewage toxics and other contaminants before they enter
the sewer system, comprehensive operator
treatment facilities. MWRA's goal is to alleviate training, sophisticated process control and mainte-
nance tracking systems, and an extensive water
the long-standing pollution associated with the
quality monitoring program at the treatment plant,
discharge ofinadequately treated sewage sludge in Boston Harbor and Massachusetts Bay. The new
MWRA
and effluent into the shallow waters ofBoston facilities will allow to meet standards set
by federal and state Clean Water Acts.
Harbor. Major components ofthe multi-billion
The new Deer Island plant began operating
dollar capital program include: new primary and when part ofthe primary treatment facilities came
secondary sewage treatment facilities on Deer on line in 1995. In early 1997, the first portion of
the secondary treatment plant is scheduled to
Island; a new discharge point for treated sewage begin treating much ofthe area's dry-weather
effluent, located 9.5 miles offshore in Massachu- wastewater flow. The entire plant is scheduled to
be completed by the end of 1999.
setts Bay; a sludge-to-fertilizer plant; and com- MWRA
In the meantime, is involved in an
bined sewer overflow (CSO) control projects. ongoing effort to understand and manage the
wastewater collection and treatment system more
effectively. The result ofthese
efforts - a more reliable system at
decreased cost— is good news for
the environment and for ratepay-
ers. Under MWRA's proposed
CSO program, many overflows
will be eliminated and water
quality improved for the harbor
and its tributaries at significantly
less cost than an earlier proposal.
Also through a reevaluation of
actual flow to the treatment
plants, planned capacitv ofDeer
Island secondary treatment
facilities will now be reduced
from 1,080 mgd to 780 mgd.
MWRA's permitting, monitoring
and contingency planning efforts
will ensure that the new facilities
operate within the law and
MWRA's NEW UfATMtNI fACIllllES (OVER I85 ACRES Of ZID'ACRE DeER IuaND.
Sewer
foundation ofits effort in the
Outfall Contingency Plan to
proactively identify and respond to
the emergence ofwater quality
issues ofconcern.
NPDES Permit Renewal
i
MWRA
is responsible for
ensuring that Deer Island treatment
plant discharges meet the various
limitations and conditions ofits
NPDES permit required by the
federal and state Clean Water Acts.
Because some limitations and
conditions, including effluent
requirements based on secondary
treatment, cannot be met until
completion ofthe new secondary
treatment facilities on Deer Island,
interim limitations have been
established in the Boston Harbor
A MONIIOItINC CHEW Of SCIENIISIS lAKES WATEIt SAMPLED FROM MASSACHUSETTS BaY. Case. Meanwhile, MWRA's permit
expired in March 1992, but remains in full effect
safeguard the region's public health and environ- pending the issuance ofa renewal permit. MWRA's
mental resources.
renewal application was filed in September 1991
The Monitoring Program and updated in June 1994. The EPA is expected to
MWRA monitors sewage influent and effluent issue a draft ofa new permit in early 1997 to cover
quality and the resulting impacts on Boston new plant and outfall operations.
MWRA
Harbor. Since 1992, has also been The NPDES permit renewal process was an
monitoring water quality, sediments and marine important element in the development ofoptions
life in the area ofthe new outfall in Massachusetts under the design reassessment ofsecondary
Bay. The program is one ofthe most extensive of facilities and the CSO Control/System Master Plan
its kind in the United States. because planned facilities for secondary treatment
direcMtWioRnAofctohendOuucttfsaliltsMopnriotgorraimngunTdaesrktFhoerce and aalnldowCSMOWcRonAtrtoolcmoumsptlhyawvietshuftfhieciNePntDEcaSpapceirtmyitto
in partnership with the United States Geological it receives. Throughout the CSO and design
MWRA
Survey (USGS). Data from the program are reassessment planning processes, paid
published by MWRA and submitted to the state's close attention to the Clean Water Act regulations
Executive Office ofEnvironmental Affairs, the driving the permit to ensure that these regulations
Federal District Court and EPA, among others. will be met, while at the same time working to
avoid costly construction ofunnecessary facilities.
Monitoring program results have improved
the public and scientific community's knowledge In a process described by federal regulation,
ofthe sources and movement ofcontaminants in EPA will circulate a draft permit for public review
the bay from MWRA discharges, as well as from and comment prior to issuing the final permit.
other sources. The focus is on the ultimate fate of Outfall Contingency Plan
these contaminants. This understanding will be
The Outfall Contingency Plan describes the
essential in distinguishing any potential impact of criteria and process by which MWRA would
MWRA's outfall from that ofothersources.
proactively identify and respond to the emergence
MWRA's outfall monitoring program is an ofany unexpected water quality issues associated
important component ofits effort to effectively with the discharge ofsecondary-treated effluent
track and manage treatment plant performance in into Massachusetts Bay. The foundation for
compliance with its National Pollutant Discharge contingency planning is the ongoing monitoring
Elimination System (NPDES) permit and the program. To date, all studies ofpotential impacts
SjiWER
have concluded that the effluent discharge will
meet water quality standards necessary to protect
the bay's marine environment. Uncertainty always
remains, however, and other factors could affect
water quality. The Contingency Plan seeks to
provide a framework for sorting out those causes.
Now in its operative form, the Contingency
Plan identifies relevant water quality issues,
specifies numerical or qualitative thresholds that
can suggest that effluent quality and/or environ-
mental conditions may be changing or might be
likely to change in the future, and identifies
applicable responses, including appropriate
changes in operations and/or maintenance ofDeer
Island facilities. The plan covers six potential
sources ofenvironmental impact: nutrients,
organic contaminants, toxic material, pathogens, In 199Z, Chews wohkinc from a barge anchored in
solids, floatables; and has provisions to incorpo- Massachuutts Bay inwaueo a 55-itiHrpiPE oiffusEit system
rate additional unexpected issues ifnecessary. along IHE last 6,600 FEEI OE THE EFFLUENT OUIFALL TUNNEL.
MWRA (Above) a cap that will top one of the users awaits placement
developed and distributed a first draft ON the deck of the barge.
ofthe Contingency Plan to appropriate state and
federal agencies, MWRA's Advisory Board, the secondary treatment facilities to include batteries
Wastewater Advisory Committee (WAC) and A and B and only part ofbattery C while still
environmental and community groups in March meeting all Clean Water Act requirements.
MWRA
1995. met with various organizations and Given the relatively small incremental capital
worked extensively to revise the draft in response cost in relation to its benefits, the study recom-
to a wide variety ofcomments. Public meetings to mended that the Authority construct all, rather
MWRA
discuss the revised Plan will be scheduled for than only part ofbattery C. pursued and
early 1997. ultimately received approval from state and
federal regulators as well as the Federal Court to
Deer Island Design Reassessment implement this recommendation. While still
In 1993, with the encouragement ofthe saving at least $165 million in capital construction
Authority's Advisory Board and WAC, MWRA costs, full buildout ofbattery C provides: in-
began a study to reassess the overall capacity creased flexibility to accommodate reasonably
foreseeable future flow and load increases; and
requirements ofthe DeerIsland treatment plant
uniform/symmetrical facilities for ease ofopera-
using actual data on influent flows and loads',
tion and maintenance.
metering and modeling work completed by the
CSO program, and new information on alternative
treatment technologies. The specific goals ofthe
study were to maintain MWRA's commitment to 1 The Deer Island treatment plant was origi-
nally sized in the 1988 Secondary Treatment
meeting Clean Water Act requirements, evaluate
Facilities Plan (STFP). At that time, reliable flow
the potential use ofinnovative/alternative tech-
and load data were not available, so estimates had
nologies and reassess the need for secondary
to be used. Actual flow and load data collected
treatment "batteries" C and/or D.^
since 1988 demonstrate that these estimates were
Completed in 1995, the study found that: too high.
actual flows and loads are lower than the esti- 2 The 1988 STFP provided for secondary
mates used in the 1988 Secondary Treatment treatment in four "batteries" - designated A
Facilities Plan (STFP); the technology selected in through D. Conceptual design was completed for
the 1988 STFP (conventional primary treatment all four batteries: construction ofsecondary
with activated sludge for secondary treatment) batteries A and B began in December 1992.
remains the most "value-effective" choice; and Operation ofsecondary battery A is scheduled to
due to the revised flows and loads based on actual begin in early 1997. followed closelv bv the
MWRA
data, could reduce the size ofits planned completion and start ofoperation ofbattery B.
Sewer
Combined Sewer Overflows (CSOs)
AND System Master Plan MWRA WASTEWATER PROIECTS
In December 1994, following an extensive
public participation process, the MWRA completed 1986: MWRA begins plan to upgrade regional
and submitted its final conceptual plan for CSG sewage treatment facilities
control in compliance with the Federal Court
schedule for the Boston Harbor Case. The $370 1989: Boston HarborProject construction
million conceptual plan differed dramatically from begins.
the 1990 CSG Facilities Plan, which proposed a 1990: CSO plan recommends $1.3 billion
$1.3 billion deep-rock storage tunnel for CSG worth oftunnel storage.
control. The new approach is based on a better
1991: Inter-island and outfall tunnel
understanding ofsewer system flows and loads
construction commences.
from a system-wide wastewater metering network,
ongoing system improvements and evolution ofthe Sludge discharges to harbor cease.
CSG regulatory framework. In October 1996, 1992: MWRA begins monitoring Massachu-
MWRA completed a Draft CSG Facilities Plan/ setts and Cape Cod Bays to establishbaseline
Environmentallmpact Report, moving the plan for
data.
CSG control forward to the next step.
1993: Secondarytreatmentplant construction
Together with two earlier phases ofMWRA's
begins.
CSG control effort, the new plan will decrease CSG
volume to 500 million gallons annually (an 84 1994: MWRA revises CSO control plan; cost
percent reduction from 1988 conditions). Along is $370 million.
with these decreases, the portion ofthe CSG flow
1995: Primary treatment plantbegins
that is treated will rise to 96 percent. operating.
State/federal regulations, and Federal Court,
approve plan to reduce planned secondary
treatment plant size.
Draft ContingencyPlan completed.
1996: MWRA completes Draft CSO Facilities
Plan/Environmental Impact Report.
Effluent outfall tunnel boring completed.
1997: Distribution offinal ContingencyPlan.
Massachusetts Secondary treatmentbegins.
Water Resources Authority EPA expectedto issue newNPDES draft
The MassachusettsLegislature created permit.
MWRA in 1985 to manage water and sewer 1999: Scheduled completion date forwaste-
watertreatmentfacilities.
services for 2.5 million people and 5,500
businesses in 61 communities. While the MWRA. offers a wide varietyofinformational
materials on theregion's waterandsewer
Boston Heirbor Project is the bestknown systems and thenaturalenvironment. Tofind
ofMWRA's projects, the Authority also out what's available, contactMWRA'sPublic
AffairsDepartment at:
maintains 400 miles ofwaterpipes,
Massaghusetts Water
aqueducts and tunnels, and 228 miles of
Resources Authority
sewerpipes. Also underway are projects to
CharlestownNavyYard «
control combined seweroverflows, provide
100FirstAvenue
adequate water deliveryandmeetall federal, MA
Boston, 02129
state and localwaterand sewer standardsr 617 242-6000