Stabilize Paw Paw Tunnel and Boardwalk
The National Park Service will undertake work during 2007 at the Paw Paw Tunnel, Chesapeake and Ohio Canal National Historical Park. The scope of this project addresses deteriorated masonry, handrails and wooden towpath structures leading to and within the Paw Paw Tunnel. The project was developed from the Condition Assessment and Preservation Planning report prepared in 2004. This detailed report identified a series of deteriorated conditions and their root causes. This project is designed to repair the deficiencies and address their causes.
Proposed work will be replacement in kind, but with sustainability in mind. Approximately ten wrought iron handrail standards have been identified for replacement. They will be replaced with stainless steel which will be painted black. Five to ten percent of the 625 hand railing cross timbers will be replaced. Preservative treated wood is being considered to resist the perpetually moist environment within the tunnel. Brick work for the towpath retaining wall will be replacement in kind. The brick liner of the tunnel barrel will be selectively repointed. Type N mortar will match color and texture. The portals will receive vegetation removal and treatment. Mortar joints will be raked and repointed with type N mortar, matching color and texture of existing mortar. Extant drainage structures will be cleaned and restored to proper function. Towpath drainage and water seepage within the tunnel will be addressed to correct uneven and wet walking surface. The water also has hastened deterioration of towpath components within the tunnel. All deteriorated towpath retaining boards will be replaced in kind as needed. North Portal Boardwalk (exterior) will have selective repairs in kind. Tunnel access shafts and drainage troughs will be inspected. The troughs will be cleaned of debris, thus reducing the amount of water seepage into the tunnel. The access shafts will be inspected and probed. Any deficiencies will be noted and addressed in a future project.
The park's Interdisciplinary Team reviewed the project for impacts to natural and cultural resources. The project does not pose any serious or long-term effects to the environmental, historical, cultural, archeological, or visual resources. It meets categorical exclusion #C.4 – Routine maintenance and repairs to cultural resources sites, structures, utilities, and grounds if the action falls under an approved Historic Structures Preservation Guide or Cyclic Maintenance Guide, or if the action would not adversely affect the cultural resource.
The project also meets the National Historic Preservation Act/Section 106 Programmatic Agreement, Exclusions #IV.B 1 – preservation maintenance (housekeeping, routine and cyclic maintenance, and stabilization) as defined in DO-28, and; #IV.B 9 – Rehabilitation work limited to actions for retaining and preserving, protecting and maintaining, and repairing and replacing in kind materials and features, consistent with the Secretary of Interior's Standards for Rehabilitation and the accompanying guidelines.
For further information about this project, please contact Exhibits Specialist, at 1850 Dual Highway, Suite 100, Hagerstown, MD 21740.