By Bill McDonald, director of Planning and Special
Programs for Waggoner Engineering (www.waggonereng.com),
Jackson, Miss., and Robin Hoban, southeast regional sales manager for
EarthData International (www.earthdata.com),
Frederick, Md.
In 2003, the Mississippi state legislature created the Mississippi
Coordinating Council for Remote Sensing and Geographic Information
Systems. Recognizing that activities by state and local governments
rarely impact isolated jurisdictions, the state took the extraordinary
step of tasking the council with developing Mississippi Digital Earth
Model (MDEM), a statewide database and common source of geospatial data,
to improve decision making and thus save time and money in the
operations of state and local government agencies throughout
Mississippi.
Upon its creation, the Mississippi Coordinating Council for Remote
Sensing and Geographic Information Systems was tasked with developing
standards and processes that would make it easier for geospatial
information users to pool resources to obtain and disseminate a variety
of data sets with minimal duplication of effort. The council invited
participation from the private and public sectors, including
representatives from federal, state and local government agencies. Key
participants at the state level include the Mississippi Department of
Environmental Quality, Department of Information Technology, and
Department of Transportation (DOT); the Mississippi Development
Authority; and several other agencies, including the Institutions of
Higher Learning (representing the state’s eight public universities).
The Mississippi Municipal League and the Mississippi Association of
Supervisors represent the state’s counties and municipalities on the
council. Joining in the collaboration is a variety of federal agencies
active in the state, such as Federal Emergency Management Agency, U.S.
Army Corps of Engineers, National Oceanic and Atmospheric Administration
(NOAA) and NASA Stennis Space Center.
“From the outset, we saw participation from
personnel at all levels of government as crucial to the council’s
success,” explains Joel Yelverton, assistant executive director of
the Mississippi Association of Supervisors, which represents the
interests of all 82 counties in the state. “Broad participation is
requisite to ensuring that the MDEM serves the diverse needs within
our state.”
The council’s foremost goal was to develop and maintain the MDEM,
which includes seven core geospatial information layers that are in
alignment with the layers identified by the National States
Geographic Information Council:
1. Geodetic Control
2. Digital Orthophotography
3. Digital Elevation Model and Contours
4. Property Ownership
5. Hydrography
6. Transportation
7. Governmental Boundaries
With cost sharing identified as a major advantage, Mississippi saw
MDEM as the foundation upon which nearly all statewide geospatial
activities would be based. Accessible by both the public and private
sectors, MDEM would enable businesses and government agencies alike
to manage resources more efficiently and to make better-informed
decisions. The council designed MDEM to satisfy a wide range of
applications, including land-use planning, economic development,
regulatory compliance, transportation design and homeland security
activities.
MDEM development has been a complicated and expensive project due to
its statewide scope. With an eye toward ensuring the long-term
continuity of the project and minimizing its cost to the state, the
council established a government-industry partnership. This
arrangement supported a contracting structure that allowed
Mississippi to respond quickly when federal funding opportunities
became available. It also forged relationships with geospatial
service providers committed to completing the endeavor.
These two major council initiatives—developing MDEM and creating an
industry-government partnership—have paid off faster than anyone
expected, most notably by positioning Mississippi to respond quickly
in the wake of Hurricane Katrina.
Developing a Statewide Map
In 2004, the council procured the services of Mississippi Geographic
Information (MGI), a private entity formed by three companies:
EarthData International, Waggoner Engineering and Watershed
Concepts. Together, the companies could provide the end-to-end
services required to bring MDEM to fruition.
EarthData (www.earthdata.com) is a full-service geospatial mapping
firm operating a variety of aerial sensors worldwide. Waggoner (www.waggonereng.com)
is an engineering, planning and surveying company specializing in
implementing civil works programs in the southeast United States.
Watershed Concepts (www.watershedconcepts.com) is a water resources
management firm with extensive experience in geographic information
system (GIS)-based hydraulic and hydrologic modeling.
The council reasoned that by having MGI under contract, the state
would be well situated to pursue geospatial funds, which often are
known to present themselves on short notice. Such was the case in
2004 when Mississippi became a cooperating technical partner with
the Federal Emergency Management Agency (FEMA) to update its Digital
Flood Insurance Rate Maps (DFIRMs). This became the first MDEM
mapping project conducted by MGI on the council’s behalf.
In the 2004-2005 flying season, EarthData deployed its Leica ALS40
(later upgraded to the newer ALS50) light detection and ranging (LiDAR)
sensor aboard a Cessna 310 aircraft to acquire the elevation data
needed for DFIRM updating. Flying at an altitude of 11,000 feet, the
LiDAR device collected elevation points at a 5-meter post spacing
with horizontal and vertical accuracy of less than 10 centimeters.
Elevation data were acquired in separate missions for the three
coastal counties.
MGI completed the preliminary DFIRMs for
Harrison County just two weeks before Katrina hit, although FEMA and
the state decided to withhold their publication until a long-term
plan for coastal recovery could be developed. As rescue activities
evolved into recovery and rebuilding in the weeks and months after
Katrina, LiDAR elevation grew in importance among available data
sets. At the request of FEMA, EarthData accelerated its production
of the LiDAR data sets covering Jackson and Hancock counties and
delivered them to the council well ahead of schedule.
Somewhat remarkably, these three counties were the hardest hit by
Katrina. The data sets wouldn’t have existed if not for a
contracting relationship established more than a year earlier by the
council.
“FEMA was the most interested in using the LiDAR (after Katrina),”
explains Cragin Knox, remote sensing and GIS coordinator for the
Mississippi Department of Environmental Quality (MDEQ). “The agency
used the new elevation points to map the location of the debris
line, which represented the high-water mark of the storm surge.
Later, FEMA acquired its own LiDAR and compared the two data sets to
calculate the three-dimensional volume of the debris so that
clean-up efforts could be planned.”
The newly acquired elevation data played another crucial role in the
three counties by helping to jump start rebuilding efforts there. A
coastal area struck by a hurricane often faces a “hurry up and wait”
dilemma regarding re-construction of homes and buildings. Owners of
houses and businesses usually are eager to replace structures so
their lives can return to normal, and they sometimes are under
pressure to use disaster relief funding while it’s still available.
On the other side of the coin, the hurricane’s storm surge often
re-writes flood zone maps. Builders typically need updated
information to decide where and how to rebuild structures to ensure
they’ll be out of harm’s way in future storms and also qualify for
flood insurance. Fortunately for Mississippi, FEMA had the new LiDAR-derived
contour maps in hand, allowing it to quickly publish Advisory Base
Flood Elevation Maps. These topographic maps guided property owners
in determining if they needed to elevate or relocate their new
houses and buildings for flood insurance purposes.
Council Still Paying Dividends
More than a year later, the council continues to play a critical
role in assisting Mississippi as it continues the rebuilding process
and begins preparing for future geospatial data needs—and
hurricanes. The statewide orthoimagery project, originally tabbed as
the base layer for the MDEM but delayed for funding reasons, became
a priority for the council three months after Katrina. Mississippi
DOT found $1 million in seed money that had to be used in 2005. At
the council’s urging, NOAA and several other agencies also
contributed funds in time for the mapping to begin during the
2005-2006 flying season.
“This was another project that we couldn’t have organized if we
didn’t already have the mapping contract in place with MGI,” says
Knox.
EarthData flew nearly two-thirds of the state during the short
2005-2006 leaf-off season, collecting digital color imagery with a
Leica ADS40 sensor. The natural-color, seamless orthoimagery will
offer a 1:4,800 map scale and 2-foot pixel resolution. The southern
third of the state will be imaged in the coming flying season after
most of the hurricane debris has been removed from the coastal area.
The council will distribute the orthoimagery at no cost to member
organizations, including counties and municipalities, and the public
will have access to the data in the near future.
Another agency that grew in its appreciation of geospatial
information following Katrina was the Mississippi Military
Department. It found money to fund part of the LiDAR acquisition
over a 2,000-square-mile area surrounding one of its major
facilities north of Harrison County, which had received damage from
the hurricane. MGI collected the data in early 2006, along with
additional elevation data elsewhere in the state for the DFIRM
project. In addition to its role in flood map updating, the LiDAR
files will be supplied to other council participants for coastal
management, erosion mapping and other projects.
Concludes Knox, “After Katrina, everyone saw all the things GIS
could do in a real-world environment—things we didn’t even know
could be done on the fly—and that provided the impetus to get other
projects started.”
