Exxon's Pegasus pipeline crosses 18 watersheds for Arkansas drinking water sources

exxon pegasus pipeline arkansas map
© Arkansas Times

Following the March 29 rupture of the Exxon Mobil Pegasus pipeline in Mayflower, Arkansas, some Mayflower residents were unaware the pipeline ran beneath their homes.

The Arkansas Times' Sam Eifling, David Koon and Elizabeth McGowan recently followed the path of the pipeline across Arkansas to see what sorts of environments and communities could have potentially been affected by a rupture that occurred in Mayflower.

The Pegasus spill surprised many people in Mayflower, in part because many of them had no idea they were living atop an oil superhighway. So we got to wondering: Where does the Pegasus go? To find out, we traced its path using maps publicly available from the federal agency that regulates pipelines, the Department of Transportation's Pipeline and Hazardous Materials Safety Administration (PHMSA). We got precise with Google Earth, following the pipeline's easement — the broad, bald line where trees are kept off the pipe — through the 13 Arkansas counties the Pegasus crosses on its way to Texas. From satellite images, we could see what another break in the Exxon pipeline could directly threaten: pastures, national forest, rivers, creeks, homes, churches, at least one school, this golf course. It also crosses watersheds for 18 drinking water sources that, together, serve about 770,000 people, a quarter of the state's population.

One major area of concern that the pipe crosses the important Lake Maumelle Watershed, which is the source of drinking water for Little Rock.

Up state Highway 113 near the western side of Lake Maumelle in Pulaski County is a "Jesus Saves" sign tacked to an oak tree. The wooden, hand-lettered sign points like a welcoming arrow to an opening in the forest where hikers can merge onto the Ouachita National Forest Trail, which wends its way along the northern edge of the impound lake.

This section of the trail roughly parallels the 13.5 miles of pipe that snakes through a watershed that provides water for 400,000 people in and around Little Rock. About one in seven Arkansans drinks, bathes, cooks and cleans with water from the reservoir.

Like the drone of cicadas and the babble of creeks, the Pegasus — with its distinctive red, yellow and black markers — is pretty much a constant hiking partner. Sometimes the trail runs right atop the buried spine of the pipeline itself. In places, rain has rutted gullies in the reddish soil, exposing the top of the pipeline to the elements.

Expansive views of the 8,900-acre lake are never far away. At points, the Pegasus skirts within 600 feet of the lake's edge. West of Highway 113 it's easy to count the spots — one, two, three — where the Pegasus crosses the Maumelle River, which Little Rock's water utility dammed in 1957 to create the lake. East of Highway 113, the Pegasus runs through miles of rugged, steep terrain without road access. At least half a dozen robust creeks drain that area, carving a direct path to the lake below.

There's only one shut-off valve for the Pegasus in the 88,000-acre watershed, a fact that makes Central Arkansas Water nervous. The valve is at the western end of Lake Maumelle and would require at least one Exxon representative to drive to the site to manually close it. The utility figures at least two hours would pass from the time a rupture was detected to the time the valve was closed. By then, the utility estimates that about 1.2 million gallons of oil could escape from the pipeline into the watershed.

Read the rest.

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