DuPage forest district may spend $128,000 to save endangered dragonfly

It's a little bug causing a lot of fuss.

The federally endangered Hines Emerald Dragonfly makes its home at Waterfall Glen Forest Preserve, not far from Argonne National Laboratory near Darien.

And when the Illinois State Toll Highway Authority began building the I-355 extension in 2006, it partnered with the U.S. Fish and Wildlife Service and the DuPage County Forest Preserve District to make sure the bug was kept safe.

According to the wildlife service, saving the dragonfly is important. Its role in the ecosystem is to eat smaller flying insects, including mosquitoes, biting flies and gnats. In its immature stage, it serves as an important food source for larger aquatic animals such as fish. They're also excellent water-quality watchdogs.

So to protect and restore their Waterfall Glen habitat, workers removed 16 acres of invasive brush, such as European buckthorn. Eventually, however, they discovered an even bigger problem.

“The brush was so thick you could barely walk through it and it was very difficult to tell what was underneath,” said forest preserve ecologist Tom Velat. “But there was an erosion gully (and) that soil was moving like you wouldn't believe.”

The erosion originates from a stormwater culvert underneath railroad tracks near the preserve. Then, both water and the soil it picks up flow toward Emerald Marsh inside Waterfall Glen, threatening the habitat where the dragonflies live and breed.

So to ensure the endangered insect keeps thriving, conservationists must slow erosion on the steep land with a project that could cost up to $128,000.

This week, the forest preserve discussed accepting a grant of about $43,000 from the Illinois Natural Resources Conservation Service for this effort. The tollway authority also will pay for a matching grant of up to $65,000.

“Our plan is to make that water move slower over the slope, with a series of check dams, sills and directing water flow through vegetative swale,” Velat said. “That will maximize stormwater going into the soil and minimize soil flowing into Emerald Marsh.”

If officials approve the grant agreements, the forest preserve district must pay about $20,000 for services, including removal of invasive species, buying and planting native seed. Velat said this is necessary to make sure the same problem doesn't happen again.

The forest preserve board is expected to approve the grant agreement Sept. 6, officials said. No commissioners expressed opposition to the project Tuesday.

If approved, Velat said work is slated to start late next spring and last two to three months. In the meantime, workers have planted grass to temporarily stabilize the erosion.