Now they have a plan and an ally in the battle.
The Clemson University Restoration Institute is conducting an ecological study of the 2,200-acre preserve. Once it's finished, a final design plan will be presented for approval.
"We are holding up going any further, getting permits, until we see what the ecological restoration study had to say," said Larry Morris, the city of Aiken's director of public works.
The city earmarked $3.5 million from the local option sales tax to fund the project, which calls for placing gabions -- stone-filled baskets used to stabilize soil and prevent erosion -- along a portion of Sand River.
For several decades, the city and the Hitchcock Woods Foundation have been working together to try to solve the erosion problem in Sand River, which is caused by storm water drainage.
"The problem has been more difficult than either imagined it would be," said Doug Rabold, executive director of the foundation.
So the foundation recommended bringing in the Clemson institute, which consists of experts in civil engineering, landscape architecture, ecological restoration, geology, hydrology and sedimentation transport.
"That's what has been lacking is this interdisciplinary approach to solving this very complicated problem," Mr. Rabold said.
More than two years ago, the city and the foundation agreed to bury a 10-foot diameter storm water pipe about 7,500 feet into the woods from the point of runoff in an effort to circumvent the river and channel the storm water directly into Barton Pond.
But city officials discarded the plan "as not being the best or the most economical option," Mr. Morris said.
In 40 years, storm water flows "have literally changed the landscape of Hitchcock Woods," said the foundation's executive director.
Drainage from the downtown and South Boundary watersheds have eroded the canyon's banks, creating sheer cliffs.
As large quantities of fast-moving storm water deteriorated the sandy river bank, it carried silt downstream, infiltrating wetlands. Barton Pond, once a favorite fishing and swimming area, is filled in by sediment from the river, and Cathedral Isle swamp is now being affected, Mr. Rabold said.
"The foundation is concerned that storm water impacts on Sand River have negatively impacted habitat and flora and fauna," he said, adding that the canyon is unnatural and unsafe.
However, Mr. Morris and Mr. Rabold said, stabilizing the ravine is a small part of Clemson's overall restoration study, which is being spearheaded by Dr. Gene Eidson, whose organization, the Southeastern Natural Sciences Academy, restored Phinizy Swamp.
Mr. Morris said the study should be finished by the end of the year.
Reach Michelle Guffey at (803) 648-1395, ext. 110, or firstname.lastname@example.org.