GIS SUPPORT OF COMPREHENSIVE
WATER QUALITY IMPROVEMENT PROGRAMS
Michael Sweeney
Thomas Quinn
Barbara Quinn
Timothy Ingram
Richard Allen
Richard Hammond
Alan Smith
Abstract
Hamilton County, located
in southwestern Ohio, is a mixture of highly developed urban,
suburban, and rural areas. Since the founding of Cincinnati, the
first area settlement, over two centuries of development, use
and abuse have produced wide degrees of degradation within the
approximate 400 square mile area. With regard to water quality,
significant contrasts are also reflected by the unique presence
of both a state and national scenic river and an adjacent stream,
recently listed among "the most endangered urban rivers in
the U.S." by American Rivers (a conservation organization)
in the same county and both tributary to the Ohio River.
The water quality impacts in Hamilton
County area are significant and include 17,000 private home wastewater
treatment systems of which at least 40 percent are malfunctioning,
237 combined sewer overflows, sanitary sewer overflows, sewer
line deterioration, and aging package plants and pump stations.
Each impact has a multitude of information to be assessed, tracked
and communicated and shared with in the organization and also
externally to policy makers and the public. Each also involves
multiple agency coordination where limited resources must be focused
optimally.
To develop area-wide water quality improvement
strategies, the Metropolitan Sewer District (MSD) and the Hamilton
County General Health District (HCGHD) are participating and/or
sharing data with comprehensive watershed and county-wide risk
assessment studies along with many other agencies. These studies
are in various stages of completion and using GIS as a means of
integrating, analyzing, and presenting data. Examples of each
are briefly presented and represent GIS applications using one
or more Esri software products including ArcInfo, ArcView, and
MapObjects. Together the applications are a major part of planning,
managing and implementing an integrated comprehensive water quality
improvement program. Technology deployment pertaining to this
effort is coordinated by the CAGIS (Cincinnati Area GIS) consortium.
Also presented is the incorporation of Global Position System
(GPS) technology at MSD and descriptions and roles of MSD and
CAGIS are also presented.
Introduction
The Metropolitan Sewer District
of Greater Cincinnati (MSD) was formed in 1968 to provide wastewater
collection and treatment services county-wide through an inter-government
agreement between the City of Cincinnati and Hamilton County,
in southwestern Ohio. MSD's service area is comprised of Cincinnati
and 34 other municipalities totaling approximately 800,000 customers
through 220,000 connections. MSD also directs the City of Cincinnati
Stormwater Management Utility (SMU), which is a fee-based utility
created in 1984. Below is a brief overview of MSD.
Many water quality impacts need to be managed and mitigated and are briefly listed below. This paper outlines how GIS technology is involved and providing important information, tools and insights leading to effective water quality improvement solutions. Perhaps most consequential is that GIS is providing a communication medium among and between the practitioner and the public bringing resources and people together to address the serious challenges to water quality.
Examples of Water Quality Impacts
Cincinnati Area Geographic Information
System (CAGIS)
MSD participates in a consortium of city, county agencies and
private utilities known collectively as the Cincinnati Area Geographic
Information System (CAGIS). The CAGIS consortium policy board
is comprise of department heads or high level executives from
each member agency. Since its creation in 1989, the main purpose
of CAGIS is to create and maintain an enterprise-wide geographic
database for integration and provide the technical vision for
creating and using the GIS framework to improve information, thus,
the quality of services. The technical vision embraces the need
to bridge the islands of information by providing an open data
framework for integration; the elimination of duplicate data entry/storage
efforts; and, to improve the quality of data itself. CAGIS has
determined that more than 80% of all local government and utility
data are related to geography. CAGIS staff work with the various
departments in the planning, implementation of GIS technology,
development of standards, and application development. The Esri
suite of software and relational database management systems are
the elemental software tools employed by virtually all CAGIS participants.
CAGIS provides essential support and
facilitation roles. The effort described in this paper involves
multiple agencies, thus, an enterprise level approach is applied.
The over-arching goals of the CAGIS consortium are:
This paper presents and discusses four
important water quality improvement programs and the GIS analytical
methodologies associated with each that include the assessment
and comparison of water quality impacts and pertinent contextual
data using CAGIS. Included are results so far of the program work
with respect to various water quality impacts and the relationships
with land use, current and proposed development activities, and
other important factors to water quality. The programs include
a successful and improving infiltration/inflow reduction program,
a study of a highly impacted watershed (Mill Creek), a use attainability
watershed study that includes part of Hamilton County and involves
several adjacent counties (Little Miami River), and a comprehensive
comparative risk assessment for the county as a whole.
Stormwater Removal Program
Management of MSD's collection
system includes an aggressive infiltration and inflow (I/I) inspection
and correction program for its separate sanitary sewer system.
Along with manhole and pipe deterioration in some areas, other
important sources of I/I have been found to be unauthorized connections
of roof downspouts, and area drains on private property. Recently,
improper foundation drains connections to the sewer system have
been discovered, which is discussed later in this section. I/I
contributors are associated with basement flooding and sanitary
sewer overflow (SSO) activity. Prior to 1992, inducing property
owners to properly disconnect sources of stormwater flow met with
virtually no results. A property owner reimbursement program was
devised and coupled with an inspection and correction program
that has identified over 19,000 unauthorized connections so far
(see Figure 1). The I/I reduction and reimbursement program is
known as the stormwater removal program (SRP). The inspection
phase involves delineating study areas using the GIS, performing
site surveys as part of the inspection phase, collecting data,
and monitoring the correction and reimbursement. The site surveys
primarily including smoke and dye testing and additionally flow
monitoring and sewer televising activities in some areas. Verifying
and recording location of sewer lines and other utilities and
features are the important "data by-products" of the
site surveys. In the correction phase, homeowners are notified
of their specific violation(s) and are provided guidance regarding
disconnection methodologies. Reimbursement up to $3,000 is provided
to the property owner for the disconnection(s) once completed.
The reimbursement for work performed on private property is allowed
because of a change to Ohio state law and has been shown to be
more cost effective in many areas when compared to alternative
capital improvement projects.
As mentioned, the SRP field inspection is a data collection and analysis opportunity. The process affords:
Field data is incorporated into a sewer
system attribute data base (SSAD) and job orders are issued and
tracked through the complaint system as the inspection phase progresses.
ArcView serves as the prime data integration and analytical tool.
While helping to organize, store and analyze the data, the GIS
also helps geographically organize and track the SRP inspection
program itself as shown in Figure 1.
Figure 1: Stormwater Removal Program
districts (red denotes unauthorized connections; yellow areas
are designated SRP study areas)
Integrating Complaint History With
SRP Activity
Spatially analyzing complaint
history (particularly basement flooding), rainfall occurrences
and SRP inspection data together represented an opportunity to
determine the efficacy and fine-tune the general SRP approach
to inspection and correction. Joining the sewer system complaint
history with identified improper connection locations along with
various other relevant contextual data revealed opportunities
to further focus resources in SRP activities and for capital improvements.
Norwood and Schoolhouse Lane are briefly presented as two such
examples where further analysis of produced potential cost savings
and better long term solutions.
Norwood is served by a complex mixture
of sanitary, storm and combined sewers and is tributary to a larger
combination sewer area. The SRP inspection program in Norwood
yielded 3,500 improper connections of primarily downspouts, driveway
drains, and area drains. As the inspection and correction phases
progressed, it became apparent that this SRP area and other areas
required a different approach to be maximally effective. The area
has 3 SSO's, but only 11 correlating rain-related basement flooding
incidents in the past 10 years has occurred. Also, the presence
of sewer system cross connections in this complex service area
complicated the picture. The correction program resulted in the
installation of 300 new sump pumps. The decision was made to suspend
the disconnection of the remaining 1,100 and set aside the approximate
$2.2 million "savings" toward a capital improvement
project that addresses the SSO's. See Figure 2. The Norwood example
caused other SRP areas to be analyzed more broadly and in some
cases re-evaluated to gage the contribution of other I/I connections.
Figure 2: Norwood SRP district: yellow
is the SRP district area; green is the current study area; red
are new sump pumps; blue are improper connections; stars are SSO
locations
The Schoolhouse Lane neighborhood example
differs from the Norwood in that extensive chronic rain-related
basement flooding is reported. It is also a much smaller, less
complex area to study. The standard SRP inspection completed with
only 6 properties identified with improper connections. It was
evident that other I/I sources must be contributing to the basement
flooding. Further testing and review of sewer TV and flow monitoring
data revealed I/I flow from foundation drains and sump pumps as
indicated by the presence of clear flow in some lateral sewers.
Checking foundation drains was originally not part of the standard
inspection phase and required additional testing. Further testing
and disconnection is proceeding. Figure 3 shows the predominance
of foundation drain connections as compared to downspouts. Public
participation in the SRP program was a low 10 - 15 percent but
increased to above 80 percent once clearer information (including
maps) and benefits to the homeowner were conveyed through an improved
public information effort. The result of spatially integrating
and analyzing the available data using ArcView and tracking the
SRP program progress and field data more closely lead to better
information and improved decision-making as illustrated in these
two examples.
Figure 3: Schoolhouse Lane (yellow are
improper downspout connections; green tested OK; red are improperly
connected foundation drains)
The Mill Creek Watershed Study
The Mill Creek Watershed Study addresses a highly impacted
urban watershed. This predominately urban watershed encompasses
164 sq mi with a main stem length 28 miles and a population in
this area of about 700,000. Identified impacts include combined
and sanitary sewer overflows, major industrial activity, leachate
from 30 landfills, wastewater treatment plant effluent, 164 CSO's,
46 SSO's, stormwater runoff and numerous underground storage tanks.
Significant habitat alteration has occurred in the form of extensive
dredging, flow diversion and channelization for flood control.
In this study, GIS is helping manage and evaluate a variety of
data sets including land use, topography, hydrology, contaminant,
and discharge locations. Results show that wet weather overflows
and runoff have a significant impact on water quality but may
not be fully mitigated by CSO and SSO abatement alone. The Mill
Creek Watershed Council serving to ultimately recover is comprised
of 25 watershed municipalities along with several government agencies
including MSD and HCGHD. This council applied for and received
one of two watershed demonstration study grants from USEPA for
this study. The purpose of this watershed study is to provide
a preliminary assessment of Mill Creek integrating and building
on previous work. A major element continues to be the development
and use of GIS as a common frame of integration and reference.
Table 1 summarizes the various data sources identified in the
GIS. Figure 4 is a sample display of several ArcView shape files
depicting some the impact locations in the Mill Creek watershed.
Table 1: Mill Creek Watershed GIS data sources (data sets in gray have been integrated so far)
Figure 4: CSO's, SSO's, and abandoned
dumps in the lower reaches of the Mill Creek Watershed
Little Miami River Preliminary Assessment
of Use Attainability (PAUSE) Study
Just a few miles east of
the Mill Creek is the Little Miami River, a designated state and
national scenic river. Here, the emphasis shifts from "recovery"
to "preservation and protection". The Little Miami River
Preliminary Assessment of Use Attainability (PAUSE) Study involves
MSD, Ohio EPA, and several organizations in the evaluation and
prioritization of the point and non-point source impacts in a
high quality stream achieving full use attainment in the upper
half and nearing full use attainment in the remaining reaches.
The 1,700 sq. mi. basin, which includes a portion of eastern Hamilton
County, receives 50 MGD of treated wastewater from 20 plants and
is dominated by agricultural land use. An additional 20 - 30 MGD
is proposed over the next several years potentially further straining
the receiving stream. Contrasting with Mill Creek, little habitat
alteration has occurred, such as dredging or channel modification,
but a growing population is already beginning to adversely affect
the groundwater quality and recharge rates to the surface water.
Stream sampling has indicated higher than normal fish anomalies
and shifts in population.
With the assistance of GIS, analysis
has determined that the non-point source pollutant loadings emanating
from agricultural land use are significantly affecting water quality
and biological diversity, though each sub-watershed varies as
to the relative percentage of point/non-point contribution. Figure
5 illustrated the predominance of agricultural land use but also
the proximity of sizable urban areas of Cincinnati and Dayton
on its western perimeter. Each point source database includes
effluent data and upstream land use category percentages, whose
pollution contributions estimates are being compared. Eventually,
it is anticipated that new and previously collected data from
a total of 170 sampling locations will be integrated into the
GIS. With the data and using spatial analysis, a very powerful
(and portable) planning, analytical and communication tool emerges.
Of the many monitored constituents,
phosphorous is one of concern and loading appears primary attributable
to non-point sources. Preliminary results indicate that point
source phosphorous loadings have found to predominate during dry
weather lower flow periods. Thus, both point and non-point
sources can contribute significantly but their predominance varies
seasonally, which supports the need for a comprehensive watershed
management plan and continued data collection and evaluation.
The identified point and non-point source impacts from anticipated
development activities and proposed plant additions and/or expansions
are readily comparable and analyzed with the developing GIS coupled
with additional water quality modeling.
Figure 5: The Little Miami Watershed
Land Use Map (yellow is agriculture; red triangles are wastewater
treatment plants; green are forested; pink is urban; and blue
lines are streams)
Hamilton County Priorities Project
(HCEPP)
The Hamilton County Priorities
Project (HCEPP) is designed to reach a broad-based consensus on
action plans and collaborative strategies to address environmental
issues on a county-wide basis, including the two programs mentioned
previously. This comparative risk study is completing its first
year and is currently exploring the capability of the GIS to relate,
assess and communicate diverse and complex information to a wide
audience including civic and religious leaders, engineers, scientists,
public officials, business and industry representatives, and neighborhood
and environmental activists that posses in varying degrees of
"neighborhood" and "regional" views. Three
working groups were formed to define and clarify the impacts,
collect and analyze the data and develop proposals to address
them. Integral to the HCEPP consensus process will be CAGIS feature
data associated with environmental impacts including permitted
discharges, overflows, dry/wet weather loadings, ground water,
surface water, and natural resources and other contextual information.
The approach to assessment, prioritization, and presentation of
various county-wide water environment impacts is still under design
and its outcome will depend on data availability and will affect
new data generation efforts. As a start, previously incorporated
CAGIS data related to water and land iimpacts from aforementioned
watershed studies, other special projects as well as normal operations
will provide a important basis.
Each working group produced an Issue list from which data is being collected and analyzed for relative impact. Many of the needed data sources of pollution impacts already exists in the GIS. As the environmental assessment phase of the study progresses, reliance on the GIS as a tool will grow as more data, various people and groups and diverse interests become intertwined. A summary of the issues from the three work groups is found below.
Water Issues
Land Issues
Air Issues
Incorporating GPS Technology
Along with data, the CAGIS
consortium is sharing, coordinating, and communicating the results
of implementing new technology. MSD as a member is incorporating
Global Position System (GPS) in its routine surveying activities
and sharing the use of a new established base station. Field tests
conducted by MSD have indicated as much as 80 percent time savings
occurring over conventional surveying techniques in many common
field situations. Siting new facilities and utilities and verifying
the location of existing ones is part of normal operations. Comparable
accuracy and the ability to digitally incorporate location data
coordinates into the respective databases in a convenient fashion
benefits all users and continuously increase the quality and quantity
of data. The base station has just been placed on-line for post-processing
of collected data from roving GPS receivers. Additional receivers
are being purchased this year by other agencies. MSD is exploring
alternatives to accessing base station data in real-time through
radio frequency and/or through dial up connection(s) and through
the enterprise-wide computer network. In the interim, post-processing
of data is occurring on location at MSD.
Conclusion
MSD is continuing to achieve the benefits
of GIS as evident by its expansion into broad-based project work
as represented by comprehensive watershed evaluations and county-wide
environmental risk assessment. GIS also is continuing to help
in the day-to-day decision making process resulting in avoiding
unnecessary costs as exemplified by the SRP examples above. Successfully
involving as many people as possible in the pursuit of improved
water quality is a benefit of GIS that may be difficult to precisely
quantify but easy to defend.
Acknowledgments
Sincere thanks go to MSD
staff, especially Melissa Gatterdam, Bob Babbs, Dale Oppenheimer,
Don Sander, Jim Watson, Mark Kron, Marty Hubbard, for their contributions,
leadership and on-going support of our GIS efforts.
Author Information
Michael W. Sweeney
Deputy Director
Metropolitan Sewer District
1600 Gest Street
Cincinnati, OH 45204
Tel: 513-244-5120
Fax: 513-244-1399
email: michael.sweeney@cinmsd.rcc.org
Thomas Quinn
Director
Metropolitan Sewer District
1600 Gest Street
Cincinnati, OH 45204
Tel: 513-244-5121
Fax: 513-244-1399
Barbara Quinn
CAGIS Administrator
County Administration Building
138 East Court Street
Cincinnati, OH 45202
Tel: 513-352-1641
Fax:513-352-3557
Timothy Ingram
Hamilton County Health Commissioner
Chester Towers
11499 Chester Road, Suite 1500
Sharonville, OH 45246
Tel: 513-326-4503
Richard Allen
Principal, MAGIC
810 Matson Place
Cincinnati, OH 45204
Tel: 513-921-2568
Richard Hammond
Woolpert LLP
409 East Monument Avenue
Dayton, OH 45402-1261
Tel: 937-461-5660
Fax: 937-461-0743
Alan Smith
BBS Corporation
11238 Cornell Park Drive
Cincinnati, OH 45242-1812
Tel: 513-489-0779
Fax: 513-489-0807