FEMA identified changes to the Black River in Missouri that required new flood modeling from Highway 60 north of Poplar Bluff to the Arkansas border. Continental Mapping performed a hydrographic survey of the 46 mile river section, surveying cross sections, bridges, and drainage structures. Using GPS and an echosounder, they surveyed river edges, extended levee sections, the river flowline, 11 road bridges, 3 railroad bridges, and 13 drainage structures to provide data for updated floodplain modeling within 5cm accuracy.

1. CONTINENTAL MAPPING
Mapping from Earth, Sky and Space
www.continentalmapping.com
Madison, Wisconsin
Indianapolis, Indiana
Kansas City, Kansas
St. Louis, Missouri
FEMA had identified changes along the Black River in Butler County, Missouri
since the last modeling and floodplain mapping effort completed in the 1970s.
This led them to believe that the current levee in Poplar Bluff was no longer
adequate in the event of a flood. This concern instigated a new flood modeling
effort which required a hydrographic survey. The project ran from Highway 60
just north of Poplar Bluff, Missouri, to the Arkansas state line.
The hydrographic survey requirements included surveying numerous river
cross sections and the primary flow line via single beam echosounder as
well as surveying over a dozen car and railroad bridges and numerous
drainage structures. Completing the survey required coordination with
local authorities such as the local railroad company. To meet FEMA’s
requirements, Continental Mapping’s survey team utilized dual frequency GNSS/GPS
receivers. RTK corrections were completed using the Missouri Department of Trans-
portation’s Virtual Reference System (VRS). All coordinates were captured to within
5cm accuracy.
LOCATION: Butler County, Missouri
YEAR COMPLETED: 2014
OBJECTIVE: Develop new hydrologic modeling for 46 miles of the Black River
The Continental Mapping survey team performed the following:
• Set 6 temporary control points and performed a static GPS survey
• Surveyed 19 river cross sections (water’s edge)
• Surveyed 9 extended river cross sections (top of levee)
• Surveyed the flowline of the river using a single beam echosounder
• Surveyed 11 roadway bridges on the Black River
• Surveyed 3 Union Pacific Railroad bridges
• Surveyed 13 drainage structures along roads, highways and side channels
Key Points:
• Timeliness: Completed the survey in very early spring to meet the schedule
• Flexibility: Defined the scope to meet the modeling needs of the engineer
• First Time Right: Products were delivered and accepted without adjustments
• Breadth of Tools: Utilized both echosounder and RTK to complete survey
FEMA Hydrologic Surveying