Geospatial technologies integration / management
Ricardo Salazar
P.E., GIS Project Manager
Metropolitan Water District of Southern California
700 North Alameda Street
Los Angeles, California 90012
Introduction
The primary concern for a Project Manager when managing a GM project is to utilize the
technology to its full extent. Several concurrent technologies can be used and combining them
will impact all project phases, moreover they will impact the usability and life of the application,
total cost and return on the investment.
Being responsive to client needs and any organizational changes required to meet those needs
should be a priority in today's highly competitive environment. Applications, systems and data
integration that will allow expedient and accurate access to the information is a vital component
of application development.
The evolution and availability of non-traditional types of data such as CAD drawings, raster
images, video, spatial information or in general complex data, has generated end user demand to
use these sources to extract better information. For example, a potential customer looking for
services in the web or an employee searching internally for information, prefers to use an
application with a graphic interface for ease of operation. By not providing this capability there
is a high risk of losing the customer. New technology that will allow us to manipulate complex
types of data as objects, needs to be used as we see in the new concept of Universal Servers that
is an evolution of the relational databases. Knowing when to use them and the available options
is very important for the design of the applications.
Two other technologies related to GIS that we need to be aware of, are aerial mapping and
remote sensing. Proven benefits must be weighted, and a decision made to use either or both
technologies. The right combination will provide us a better and cost effective solution. Current
in-orbit satellites fiu-nish a variety of spectral and spatial data, depending on the application the
use of one or more sources may be more beneficial. Considering that normally the information
obtained directly from the satellite companies is raw data or "level 1", we should also take into
consideration independent companies that acquire data from different sources and then process
that data (Orthorectification, Data fusion Co-Registration, large scale mosaics, elevation
extraction (DEM), tonal balancing) and deliver it in GIS ready format. The main variables to
consider when defining the data to be used, are coverage, pixel size, resolution, availability, cost
and accuracy. In a later portion of the paper we will discuss this issues and the impact that they
have on the project.
We will also discuss document management and how this technology has been integrated with
GIS. Often we see this technology imbedded in a GIS application. The tendency is to become a
paperless society due to the advantages gained such as getting fast access to crucial information,
reducing the cost of "handling" information, greatly improving information decision-making,
decreasing the time workers spend processing documents and other factors. To make possible
the integration of GIS and Document Management three component technologies need to be in
place; 1. document management software, 2. imaging retrieval and manipulation software and 3.
workflow software.
Another technology used by GIS is the Global Positioning System (GPS) that can be used to
acquire different levels of information, from very accurate centimeter location to 2-5 meter
accuracy. This capability will allow us to capture precise base map information using
differential kinematic GPS, or city street lights mapping to one meter accuracy by using
different GPS receivers and stationing times. A sample of dynamic integration of GIS and GPS
will be a navigational system used by some rent-a-car companies to travel from one location to
another, they show the city map and the actual location of the car, including instructions to get to
the destination.
We also need to keep up to date with a variety of communication technology such as local,
remote, mobile, and Internet technology, alone with an understanding of their impact in the GIS
application. As part of the application design, we need to define where the data will reside, what
type of data can be transmitted based on the availability, communications speed and cost. For
example, to keep track of vehicle location containing hazardous materials, the communications
aspect is the most costly, specially if it is in a remote area or one not covered with a
telecommunications network. The Internet and object oriented technology has allowed us to
deploy applications for internal and external users. Considerations of confidentiality, security
and performance should be addressed.
For software systems that are very closely related with GIS like Computer-Aided Drafting
(CAD), Facilities Management (FM), Supervisory Control and Data Acquisition (SCADA), we
will see that their primary integration with GIS is as a graphic presentation or analysis tool for
integration of graphic and text data. An important part of this discussion, is what needs to be
considered in each system to facilitate the integration of the parts, to achieve an integrated
information management system.
The discussion then will cover critical factors that should be considered within each technology,
when evaluating what to use to satisfy the application requirements. By considering these
factors, it will help us to achieve client satisfaction, integration with other company applications,
low cost and a good return on the investment.
Most of the observations included in this paper are based in the present development of GIS at
the Metropolitan Water District of Southern California (MWD). MWD provides approximately
60% of the water used by the nearly 16 million people living on the coastal plain of Southern
California between Ventura County and the Mexican border, covering about 5,200 square miles
and including 240 cities and unincorporated areas. Several reservoirs, filtration plants and an
almost 1,000 mile pipeline distribution system that includes the Colorado River Aqueduct are
used to satisfy the yearly average of 1.8 million acre-foot water demand (one acre foot= 325,851
gallons).
