Jinan Li, Steven Lane, and Tom McMurtrie
ArcView Application for Solid Waste Collection
Districting
Abstract: The City of Ann Arbor Information Services Division
has developed a districting application for the Department of Solid
Waste. This ArcView application is built on the principles of
districts and subdistricts. The Department of Solid Waste employees
use this tool to more efficiently and quickly manage the scheduling
of the residential solid waste collection routes. The department's
customer accounts are assigned to any of the 5 districts and 36
subdistricts. Based on an existing GIS database, a variety of project
plans can be created, modified and stored. The system has the
advantages of a easy operation, robust functionality, automatic
reporting and mapping, and can easily be adapted to other
districting applications, such as Voter Districts, Police and Fire
Districts, etc.
Introduction
The City of Ann Arbor Solid Waste Department operates
residential and commercial refuse collection operations with
municipal crews. As in the case with many other cities, Ann Arbor
is now facing increasing budget constraints, and has had to look
closely at all operations, including Solid Waste. In 1990, the City
issued a refuse collection RFP (Request for Proposal) for the first
time. The Solid Waste Department submitted a proposal that
competed against the private sector for services that it had
traditionally provided. As part of that proposal, the Department
looked closely at all its costs, and made a number of operational
changes that resulted in substantial savings. As a result of those
efforts, the City came in as the lowest cost and most qualified
bidder, and won a contract to provide the services for five years.
This year, the City is repeating the process for the refuse
collection services. In order to respond effectively to that RFP, the
Solid Waste Department is now looking at additional ways to
increase efficiencies and cut costs. To do that, it has enlisted the
services of the City's Information Services Division to devise a
method for more efficient route balancing. Currently, the
Department operates 7 trucks per day on the residential refuse
curbside routes and 3 to 4 trucks per day on the commercial and
multi-family front load dumpster routes. Both of these programs are
operated five days per week. In order to increase efficiencies, the
Department is seeking to balance the work load among the five work
days, as well as the work load among the routes on each work day.
Process for Selecting ArcView
In the past, the Department has adjusted routes within work
days manually, which is a very time-consuming and inefficient
process. The individual collection days on the residential routes
have not been adjusted in over ten years. During that period,
housing in the city has experienced strong growth, particularly in
the Department's Wednesday collection area. The Department is
seeking the ability to adjust the routes on a more timely and efficient
manner, which it believes will help lower collection costs and
provide a better service to the public.
In reviewing these collection systems, both the Solid Waste
Department and Information Services Division agreed that the use
of a desktop Geographic Information System would be the most
appropriate tool. Information Services Division recommended
ArcView, which has capabilities that the Solid Waste Department is
seeking, and will allow it to adjust routes as needed from within its
own offices. With the ArcView program, the Solid Waste
Department has begun balancing the routes, and anticipates that
these adjustments will translate into savings that can be used as part
of its proposal to help it to remain competitive in the next round of
refuse collection RFPs.
Solid Waste Districting System (SWDS)
The Solid Waste Department has historically divided the City of
Ann Arbor into five geographic districts, one district corresponding
to each of the business days. Each of these days have then been
subdivided into seven or eight subdistricts, according to the
workload. Each subdistrict would be handled by one collection
truck. Wednesday's district is the only district assigned eight trucks,
with the other days' workload being handled by seven trucks. This
results in 36 subdistricts being assigned to the Department of Solid
Waste's personnel for collection. The service area of the Solid Waste
Department includes 969 tract blocks and 44,805 customers.
The SWDS emulates the above mentioned districting and
subdistricting characteristics and allows for more flexibility in the
assignment of districts. The most important feature of the SWDS is
its ease of use. The personnel within Solid Waste had no previous
GIS experience and with five to ten minutes of instruction, they
were able to begin familiarizing themselves with the operation of the
SWDS. The SWDS operates at two levels, one in which the
assignment to the district is completed and a second in order to
assign the subdistrict to each of the tract blocks within the city.
Through menu choices or button clicks, all district variables are
assigned by dragging a selection tool over the desired blocks (Figure
1).
The statistic table monitors allocations for the user, giving up to
the minute reporting on the effects the user has had on the plan.
The district statistic table shows the breakdown of dwelling units
within each of the districts, the average number within each district
or for the city as a whole, the name of the maximum and minimum
district workloads and how many blocks fall within each district
(Figure 2). With one push of a button, the user may choose to view
or not to view the statistic table. The subdistrict table illustrates the
number of tract blocks and the maximum or minimum workloads
within each subdistrict.
The data structure is designed to avoid the data duplication and
to save the disk storage. Only one copy of the census block boundary
file is maintained all the time. Actually, the SWDS creates plans to
allow the user to store many different options. At the beginning of
each session, the user will create or select a plan and the plan's
attribute table is linked to the tract blocks geographically. If the user
wishes to save the current plan, they may save under a different
name, or overwrite a previously saved plan or they may even delete
both the current or previous plans. The SWDS offers full file
management capability.
In addition to the regular districting and subdistricting, the
SWDS has a special function for setouts. Setouts are instances of
special services that the City of Ann Arbor Solid Waste Department
offer to citizens. These special services could be for reasons of
handicap or elderly persons being unable to put their refuse
curbside.
The SWDS has many other utilities for the management of
maps such as labeling street names, setout identifications, and tract
block numbers. The mapping tool lets user automatically create and
print a map zoomed to the extent of subdistrict. The created map
also includes a full view of the city and the reports to the drivers the
instance off setouts along their routes.
Conclusion
The SWDS provides the City of Ann Arbor Solid Waste
Department all of the capabilities that it had requested. It provides
an on-site independent application that is both easy to learn and use.
With the data structure, the department is able to maintain the
current plan and experiment with other districting options allowing
driver interaction in the decision making process prior to
implementation of a plan.
Acknowledgment
The SWDS was a project developed by the Information Services
Division for the Department of Solid Waste. Mr. Fred Bohl and Mr.
Merle Johnson of the Information Services Division have
contributed to designing the project and assisting with this paper.
Jinan Li
GIS Programmer
Thompson Associates
2929 Plymouth Rd, Suite 200
Ann Arbor, MI 48105
Tel: (313) 665-9500
Fax: (313) 665-4934
E-mail: Geo_Li@emuvax.emich.edu
Steven Lane
Jr. Programmer/GIS
City of Ann Arbor-ISD
100 N. Fifth Av
Ann Arbor, MI 48107
Tel: (313) 994-1849
Fax: (313) 994-3031
Tom McMurtrie
Coordinator of Recycling Services
City of Ann Arbor-Solid Waste
100 N. Fifth Av
Ann Arbor, MI 48107
Tel: (313) 994-6581
Fax: (313) 994-1816