Project Overview
Project Background
The Conway County Levee District No. 6 in Conway County, Arkansas is proposing to create an industrial site within the area known as the Oppelo Bottoms in cooperation with Conway County, Conway County Economic Development Corporation (CCEDC) and Central Arkansas Intermodal Authority (CAIA). Since the 1950s the Oppelo Bottoms Site, located south of Morrilton, has reportedly never flooded from high river levels due the protection of the levee system. Up until the Federal Emergency Management Agency’s (FEMA) last remapping of flood zones in 2019, the entire area was officially “out of the flood zone” with the FEMA designation of “levee-protected”. Like most long-time farm landowners in rural areas, willingness to sell the land was out-of-the question. That began to change in recent years, so the Conway County Economic Development Corporation (CCEDC) began plans for securing options from the owners for the purpose of offering the area for industrial and commercial development. This happened to coincide with the plans of the CAIA to locate a port on the river.
Since 2015, the CAIA has been instrumental in the pursuit of economic development in Perry and Conway counties through the development of a port on the Arkansas River and the attraction of new industries and commerce associated with a port facility. Meetings held since 2015 have laid the groundwork for port development. During the 2019 flood, the Oppelo Bottoms began to flood without substantial contribution from local rainfall, which indicated potential levee issues. A malfunctioning ground-level drainage pipe under the levee was identified as the issue. A coffer dam was completed on the inside of the levee around the source of the leak, which helped contain the high water in the Oppelo Bottoms site. Had this coffer dam not been constructed in a very short timeframe and high capacity pumps not been deployed, all of the Oppelo Bottoms could have flooded and stayed flooded for several weeks, including state Hwy 9. The flood of 2019 presented the following challenges for future development.
- FEMA’s new flood map in early 2019 labeled the Oppelo Bottoms area as entirely in the floodplain because the levee was de-accredited due to the lack of providing geotechnical and other supporting data to meet federal regulations for levee accreditation as identified in 44 CFR 65.10. An additional factor is the inability to sufficiently drain the basin by removal of inordinate amounts of collected rainfall within the basin in conjunction with simultaneous high river levels. Funding to protect the primarily farmland Oppelo Bottoms area was not in place at the time.
- Additionally, one of the largest floods in Arkansas River history occurred a few months later and lasted for several weeks. The Oppelo Bottoms stayed dry for the most part because the levee held and was never overtopped, and because local rainfall amounts were within normal ranges.
The only bridge across the river within 20 miles, the Hwy 9 bridge between Oppelo and Morrilton, would have been closed as well. South of Oppelo Bottoms, critical access highways and even the area’s only railroad line were also river-flooded and closed for several weeks. The impact of a prolonged closure would have affected the south side of the river the most because Interstate 40 and US Hwy 64 run parallel along the north side of the river, where the population centers, jobs, trucking and interstate commerce are located. Most impacted areas would have included Perry County, the cities of Perry, Perryville and Oppelo, Petit Jean Mountain State Park, and the Green Bay Packaging (GBP) paper mill located adjacent to the Oppelo Bottoms. This was the proverbial wake-up call. While the levee drainage pipe issue will be forever fixed with assistance from the State of Arkansas and the U.S. Army Corps of Engineers, the vulnerability of the region to a rain-induced flood of the Oppelo Bottoms is now abundantly clear. The core of the issue is the GBP paper mill, the largest employer in the region, has to operate as a “just-in-time” production plant (i.e., if trucks can’t get in or out on a continuous basis, the mill cannot operate). All officials agreed that the Oppelo Bottoms and Hwy 9 would have stayed under water for as long as the flood continued, which was six weeks. The mill would have essentially been sitting on an island with flood waters blocking their deliveries and their employees.
Prior to the flood of 2019, port site investigations included evaluations of several alternative locations. Seven alternative port site locations were considered and evaluated through independent professional studies commissioned by CAIA. Each of the seven different sites were considered for their economic development potential with an anchor tenant requiring port operation, GBP in this case. The main considerations were viability of the site on the river, including whether it would be approved by the U.S. Army Corps of Engineers, and on the land side whether it was developable for large-scale industrial locations and operations. After several investigations, the organizations settled on a site along the banks of the Oppelo Bottoms and were working together on this one site to develop a viable and comprehensive economic development plan for the region.
Project Description and Overview
Conway County Levee District No. 6, in coordination with Conway County, CCEDC and CAIA, have identified Oppelo Bottoms as an ideal industrial site location for the region. This site consists of approximately 1,800 acres of predominantly farmland along the Arkansas River. This site is protected by a 4.4-mile long levee system that requires FEMA certification. The project will also include construction of a pumping station to assist with internal flooding behind the levee when the flood gates are closed due to river flooding. Refer to the Preliminary Engineering Report by Garver for pump station details. Pumping infrastructure is anticipated to include installation of a stormwater pumping station, which would consist of these construction components:
- Intake structure – this structure will direct stormwater to the suction side of the pumps, screen out larger debris, and optimize the efficiency of the pumps.
- Sump basin – a sump basin be constructed on the intake side of the pump to allow for sufficient water to be available for the pump.
- Multiple stormwater pumps – high flow, low head pumps capable of passing some solids, designed for stormwater applications.
- Pump support structure – reinforced concrete structure to support and hold the pumps. The structure would direct water into the intake of the pumps.
- Discharge piping – Piping will route the pump discharge over the levee and to the Arkansas River side.
- Electrical components – Electrical motors, switches, controls and power supply for the pump operation.
- Site Improvements – Access road, fencing, and parking area at the site.
Need and Purpose
In order for the Oppelo Bottoms site to be utilized for economic development, certification of the levee with FEMA is needed, which will reduce flooding risks to Oppelo Bottoms.
FEMA levee certification consists of a detailed engineering analysis and inspection of the Conway County Levee District No. 6 Levee System following requirements of 44 CFR, Section 65.10 Mapping of Areas Protected by Levee Systems. The results of the study will define the construction requirements to renovate or replace existing infrastructure to meet the certification requirements.
As a result, CAIA, Conway County Levee District No. 6, and CCEDC plan to submit levee certification to FEMA with a goal of FEMA Accreditation, which would revise flood mapping of the Oppelo Bottoms as being outside the 100-year floodplain. Accreditation of the levee is needed to make the Oppelo Bottoms site developable as an industrial and port facility by protecting it from flooding. Additionally, this accreditation would bring the 2019 FEMA designation of floodplain for Oppelo Bottoms to the original determination of it being defined as an area “protected by a levee” and outside the 100-year floodplain. As identified in the PER, a pumping station and drainage program that can assist with removing stormwater generated by direct precipitation from the Oppelo Bottoms over the levee to the Arkansas River when flood gates are closed is needed.
Additionally, a CAIA Market Study (Cambridge Systematics, Inc., 2017) was prepared for the Arkansas Department of Transportation that documents the economic and industrial development and growth in the region. This study documents overall importance of intermodal transportation.
The purpose of the pumping station is to safely and efficiently convey stormwater from direct precipitation downstream and prevent flooding of the Oppelo Bottoms. This would allow the Oppelo Bottoms site to be developable by reducing direct flooding risks to business and prevent road closures due to flooding.