"The stone is on the National Historical Registry, so we have to be very sensitive when we do the restoration," said Sandra Walther, DNR Division of Missouri State Parks architect. "We have to make sure that we maintain the existing structure using materials and methods that were used in the original work that the CCC did in the 1930s."
In order to prepare for the project, which will replace the failing stones in the wall, Walther spent a large amount of time researching and analyzing the stone used to build the structure around the spring pool.
"I visited a lot of quarries in the area and even went down to Eureka Springs, (Ark.)," said Walther. "I was not satisfied with the stone I found at any of the local quarries, so I asked to open a quarry in the park."
Walther received permission to open a quarry near the corral located on Highway F. In November of 2007, she visited the quarry site with a stone fabricator and historical mason.
"We did a one-day excavation to see what was available and what could be used as replacement stone," said Walther. "We found stone ledge and determined that it was an exact match."
Prior to requesting construction bids for the project, Walther also visited Roaring River to tear down a portion of the wall and determine what materials were used behind and under the stone. She created final specifications and drawings for the project that gave crews directions on putting the wall back together correctly.
MTS Contracting, Inc., a Springfield-based construction crew that specializes in historical restorations, was awarded a $475,300 bid for the project. Since initial approval of the bid, three change orders have been approved bringing the total project cost to $483,997.
"This was originally a dry stacked wall," said Walther. "The dam leaked through the dry stack, and in an effort to keep the wall from leaking, crews went in and re-pointed the stone. Some of the wall has mortar and other parts are dry stacked.
"I want to take the wall back to the original dry stack wall," said Walther. "The piling along the dam was stabilized a few years ago so this will just improve the visual aspect."
A perforated pipe will be placed along the dam and one-inch gravel will be layered beneath the restored stone wall to allow any moisture that escapes from the spring pool to drain out of the wall into the hatchery raceways below instead of remaining in the wall causing the stone to crack.
Although the majority of the wall will be completed using the original dry stack method, the walk on the top of the wall requires mortar between the stones. Walther completed additional research to find an exact match for the clay and portland cement mortar used in the original construction.
"The portland cement used today is fired at a different temperature than that used by the CCC, so I had to find another solution that would closely match the original," said Walther. "I decided on a portland cement, lime and stone mixture. The analysis for that will become part of the project file in the future."
In addition to restoring the stone wall and walkway around the spring pool, Walther's project plans call for the installation of new hand rails along the falls and stairs. The new rails will be constructed using an architecture iron that will be painted black.
"When the CCC completed the stone work there were no hand rails," said Walther. "The rails have been put up sometime since the 1930s. I have found photos from the 1950s that show pipe rail in the falls area. That gave me one clue of what should be used.
"The wood railing is nice and works okay but it is not period appropriate," said Walther. "The aluminum hand rail that has been used on the steps doesn't work at all. It detracts from the historical looks of the CCC work."
The new black hand rails will only be placed where rails are currently located. On Nov. 12, crew members began measuring and marking the area above the falls for railing that will be installed there over the next few weeks.
The project plans also call for the restoration of the CCC insignia that is located on the stone wall near the falls. Walther ordered another set of specific mortar ingredients to complete that portion of the project.
"The insignia is lost in the wall right now," said Walther. "It will be cleaned and the stones that are missing will be replaced."
Earlier this year, Walther visited the quarry that has been opened in Roaring River to select the small replacement stones for the project.
"We will also repair the mortar joints," said Walther. "The mortar in the insignia is different than the mortar used on the pathway. We don't know if the CCC purchased the aggregate for the mortar for the insignia, but we do know that the aggregate is from somewhere other than the river bed."
When the project is completed, Walther hopes Roaring River visitors will not notice the restoration work that has been completed. She also hopes visitors have not noticed how damaged the wall had become over the last few years.
"I hope visitors come to the park and see the same walkway that they have for years, without the failing stones," said Walther. "We will use as many of the original stones as we can, and the old walkway will still be there. It will just be restored in a way that will allow moisture to drain away.
"The wall has been here for nearly 80 years and I hope the work we're doing here now will help it last another 80 years," said Walther. "I also hope that if any of the CCC guys, who worked on this project, were to come down to see it, they would feel I have done it justice."