CONTEXT SENSITIVE DESIGN CASE STUDY NO. 3

Danville-Riverside Bridge and Bridge Approach, Montour and Northumberland Counties, Pennsylvania

 

 

LOCATION

 

State Route 54 across the Susquehanna River spanning between Riverside and Danville in Montour and Northumberland Counties, Pennsylvania.

 

 

PROJECT DESCRIPTION

 

The project involved replacement of an existing two-lane Parker Through Truss bridge built in 1904 spanning the Susquehanna River, with a new 1,440 foot-long bridge with weathered steel haunched girders.  The approach to the old bridge from Danville was on Mill Street, the center of the town’s downtown commercial area.  The final alignment for the new bridge on this side of the river directs traffic under two blocks of the West Market Street Historic District one block west of Mill Street, creating a 320 foot-long cut and cover structure before transitioning onto the four-lane Continental Boulevard which links to other major traffic routes.

 

 

PURPOSE AND NEED STATEMENT

 

The Evaluation of Project Need report was finalized in February 1991.  This report was formally presented to the public at a public meeting in Danville in March 1991.  The purpose and need statement was not developed based on consensus with all stakeholders, since the Citizens Advisory Committee first met in September, 1991.

 

The report summarized the need for the bridge replacement as follows:

In addition to the replacement of the steel truss bridge, other project needs and objectives were identified including:

 

 

CONTEXT SENSITIVE FACTORS

 

A wide range of context sensitive issues were addressed as part of this project including the impact of the bridge approach through Danville on business in the downtown commercial area, the impact of construction on historic properties directly adjacent to the cut and cover section and on the natural environment of the river.  Aesthetics and creating a project that would enhance the identity of both Riverside and Danville were also important considerations.  Context sensitive design and construction issues which were implemented as part of this project include the following:

 

Bridge Design:  The new, 1,440-foot, seven-span, continuous composite steel girder bridge was built on new location immediately downstream of the old bridge, and includes distinctive architectural features designed to provide a clean, uncluttered appearance, while complementing the area’s historic setting.  These features include:

 

 

The communities of Danville and Riverside wanted a cut-stone arch bridge but PENNDOT determined that this was not a reasonable and prudent option because of high costs. The chosen solution utilized conventional, unpainted, grade 50 weathering steel designed with haunched girders. There are no joints over the entire 1,440-foot long bridge except at the abutments. This eliminated the associated costs for new deck joints at the piers and their long-term maintenance costs. The steel also tied into the regional iron-making heritage, satisfying one of the community design guidelines requirements. Additional benefits were gained in the longer spans and high slenderness ratios that the steel girders provide, which eliminated three piers and significantly increase the hydraulic opening.

 

Cut and Cover Design:  The “underpass” section, SR 6054, Section A14, is located on Factory Street in Danville, immediately north of the new river bridge.  The underpass provides a straight, new alignment that extends from Riverside, across the new bridge, directly through (and under) the Danville historic district, to Continental Boulevard (a four-lane, limited access facility).  By essentially isolating the roadway from its historic surroundings, the underpass allows traffic to flow safely and less obtrusively through Danville while preserving the area’s historic character.  Finally, by giving trucks and other through traffic the opportunity to bypass Danville’s Mill Street business district, the underpass has reduced congestion on this main street.

 

A major focus of the design effort was to create a “livable, visually-appealing, and historically-correct,” integration of roadway, structure, and historic neighborhood.  Like the new bridge, the underpass includes amenities and distinctive architectural features that blend the new construction with its surroundings. These include:

 

 

Protection of Historic Structures:  A significant challenge in the design and construction of the underpass was protecting the delicate historic buildings immediately adjacent and within 5 feet of the structure’s deep excavation.  Detailed designs of three approved alternate systems – slurry wall, secant pile wall, and soil-mixed wall – were developed. All three methods are complicated, rely on sophisticated technologies, involve careful construction sequencing, and require qualified specialty contractors.  The project’s construction documents specified the allowable support methods, minimum design, installation, and monitoring requirements. The required sequence of construction was thoroughly documented and integrated into the underpass design to assure the proper interface between the temporary bracing system and permanent structure.

 

The contract included the following mandatory construction requirements:

 

The contract documents provided details and specifications to control noise and vibration, and to minimize risk.  Grouting specifications were designed to provide additional foundation stabilization to the four adjacent historic homes. In addition, instrumentation systems were designed to closely monitor vibrations and any horizontal or vertical soil movements. This early detection would provide time to develop remedial or precautionary measures if shifting occurred.  The specifications also required preloading the strut/bracing system.

 

As a result of careful attention to all aspects of the design and construction, the underpass was successfully completed with no detectable soil movements and no damage claims to historic properties.  Nearly 8,000 mechanical reinforcement splices were used to construct the underpass in four phases.

 

The contractor chose to build the soil-mixed wall alternative.  Soil-mix walls consist of hardened soil-grout mixture, with steel I-beams inserted vertically at 5-foot intervals.   The soil-mix walls used to build the underpass were 3 feet thick and up to 45 feet deep.   The walls are installed from the existing ground surface prior to beginning excavation. After the soil-grout mixture gained sufficient strength to resist soil pressures, the ground adjacent to the wall was excavated.  Lateral bracing was installed between the soil mix walls as the excavation progressed to prevent excess wall deflection.  Finally, after the excavation operations were completed, the storm drainage lines were installed and the underpass structure was built using conventional reinforced concrete.

 

Soil mixed walls are normally used when very rigid excavation support is needed and when the proximity of existing structures necessitates minimal ground disturbance as excavation support is installed.  Clearances as tight as 5’ between existing residences and the 30’ deep excavation needed to construct the underpass dictated specialized excavation support measures.  Although PENNDOT selected contractors by low bid, they also had to be prequalified.  PENNDOT felt fortunate to secure a competent prime contractor that did the actual construction of the underpass and a subcontractor very familiar with the soil mixing process.   

 

Enhancement of Boroughs: The Boroughs of Danville and Riverside saw the bridge project as a revitalization opportunity for their communities. The boroughs obtained approval to use ISTEA enhancement funds and carried the architectural treatments from the bridge and underpass to Mill Street and Continental Boulevard in Danville and along the intersection approaches in Riverside including ornamental lighting, brick paving, an outdoor sound system on Mill Street, and new trees.

 

 

HISTORY OF PROJECT

 

In 1982, structural deficiencies were found during a routine bridge inspection of the steel truss carrying State Route 54 across the Susquehanna River. Critical structural members rated as substandard. Additionally, the 7-span steel truss bridge was determined to be functionally obsolete due to narrow lanes, a lack of shoulders, poor sight distances and low vertical clearance. Environmental studies were started in 1983 when the department retained the services of a consultant to develop alternatives and to conduct an Environmental Assessment. Numerous public meetings were conducted to solicit input from local citizens, community leaders and elected officials.

 

Alternatives were developed that ranged from replacement on existing alignment at Mill Street in Danville (the central business district), crossing on new location at Factory Street in Danville in the West Market Street Historic District and local neighborhood), and for what some members of the communities wanted - bypassing the boroughs altogether with a new crossing upstream. Very early in the project the West Market Street historic District was established with the Factory Street Alternative the only one determined to impact a 4(f) resource.  Eventually, the historic district was expanded to include more of the borough making both the Mill Street and Factory Street Alternatives 4(f) alternatives. The determination of eligibility for both districts preceded their listing in the register by a number of years – over five years for the Danville Historic District alone.

 

Amid escalating controversy over the identification of a preferred alternative, a public hearing was held in November 1988. The transcript of the hearing reveals deep division among the community members between the Mill Street and Factory Street alternatives with some residents believing that the existing bridge should be rehabilitated. The core concerns were perceptions that each proponent group had about their community and what was important to preserve.

 

The Federal Highway Administration elevated the project to Environmental Impact Statement (EIS) status in 1989 because of public controversy and concerns for the Danville Historic District.   The project team started over with development of project purpose and need and set out a new course. The department organized a Citizens Advisory Committee (CAC) in September 1991 to meet routinely and discuss the various aspects of the project. The CAC requested the formation of a Community Design Task Force to address community design issues, prepare guidelines for implementation, and develop design concepts, resulting in publication of “Community Design Guidelines for Replacement of the Danville-Riverside Bridge” in July 1993.  PENNDOT retained a consultant for preliminary and final design that same year

 

The draft EIS was circulated for comment in October 1992, and a second public hearing was held in November. The results were similar to the first public hearing in many regards, the community was still divided on the choice of alternatives.  There was growing concern for the historic district (a Danville Historic District was listed in 1994 incorporating the West Market Street Historic District in a larger district) and the escalation of this issue to the Pennsylvania Historical and Museum Commission (PHMC) and the Advisory Council on Historic Preservation (ACHP) through a letter writing campaign by the project opposition.

 

A lawsuit filed against the Federal Highway Administration (FHWA) in January 1998 by the Concerned Citizens Alliance, Inc. on behalf of citizens of the Market Street Historic District sought to enjoin the project from proceeding.  The National Trust for Historic Preservation filed an Amicus Brief to support the case.  In July 1998 the United States District Court ruled in favor of the FHWA and in a subsequent appeal filed by the plaintiffs in the U.S. Court of Appeals in Philadelphia, the Circuit Court in May 1999 supported the District court’s ruling.

 

To help resolve remaining concerns about which alignment entering Danville was best, PENNDOT hired a nationally recognized consulting team knowledgeable in historic preservation and commercial revitalization issues to evaluate the two alternatives under consideration, the Mill Street and Factory Street alignments and their relative impacts on historic resources and the business community.  Their mid-1995 report concluded that “The Factory Street bridge location is…the more acceptable solution to a vexing situation.”   The team identified, however, a series of measures that were needed to mitigate the impacts of this alternative that were included in the Memorandum of Agreement signed the next year and are discussed under the Resource Agencies Involvement section.

 

A new Danville-Riverside Community Design Group (CDG) of 33 members was formed in April 1996 including some members from the CAC, to address issues in final design.  A Memorandum of Agreement between FHWA, PHMC, the ACHP and the Boroughs of Danville and Riverside was signed in June 1996.  The Final EIS was approved by FHWA in July 1996 and the Record of Decision was issued by FHWA in May 1997.  Groundbreaking for the bridge came in July 1998 and a dedication ceremony for the new bridge occurred two years later in mid-2000.  The Underpass was opened to traffic about two months later.

 

 

HIGHWAY AGENCY INVOLVEMENT

 

PENNDOT initiated this project in 1982.  The agency’s involvement continued throughout the project and was critical to the evolution of events and eventual progress that occurred on the project.

 

 

RESOURCE AGENCIES INVOLVEMENT

 

The Pennsylvania Historical and Museum Commission (PHMC) had the greatest involvement of the resource agencies.  Following the listing of the Market Street Historic District on the National Register in 1984, PENNDOT asked their consultants to survey the entire Borough of Danville for National Register eligibility.  This resulted in the designation of a Danville Historic District, which encompassed the West Market Street Historic District, as eligible in 1989.  This district was formally listed on the National Register in 1995.

 

The selected alternative called for the relocation or demolition of two properties in the historic district, one of them a non-contributing element of the district.  Alternatives for treatment for the other house that was found to contribute were included in the MOA.  Another contributing property eventually was demolished once construction was underway.  The Iles House located at the intersection of Factory Street and Mahoning Street, was not needed for construction of the Underpass, but structural deficiencies inherent in the building’s design and construction posed a safety concern for its 83-year-old owner/occupant, Mrs. Ruth Iles, by the adjacent Underpass construction activities.  It was purchased for stabilization during Underpass construction with restoration work to be completed later.  Subsequent investigations of the property by the contractor and structural engineers determined it to be too severe of a safety risk for workers performing the stabilization and recommended demolition of the building.  PHMC concurred with the recommendation on the condition the MOA be amended to include the former Iles property in the boundaries of the Urban Design Plan.        

 

Other concerns of PHMC echoed those of residents and the business community in Danville who were concerned about the impacts of taking traffic off Mill Street, its possible negative impact on businesses and the potential negative impact of inappropriate new development along Front Street between the new bridge and the start of Mill Street.  Mitigation measures to address these concerns were identified in the course of the expert consultant team’s report completed in 1995 and were included in the MOA signed in 1996. 

 

The MOA called for FHWA and PennDOT to prepare an Urban Design Plan to integrate the Danville-Riverside Bridge Replacement Project into the Danville-Riverside area while maintaining the character of the Danville Historic District.  FHWA was to provide funding for PennDOT to prepare the plan including design guidelines, development strategies and potential zoning modifications to encourage the most appropriate development for the gateway into the borough.  FHWA was also to provide funding to PennDOT to develop a traffic and parking plan to focus on the needs of pedestrians and downtown shoppers and to hire a planner to work in conjunction with Borough officials to maintain the economic vitality of the downtown area.

 

All the above activities stipulated in the MOA have been completed except for the proper disposal of the vacant land along Front Street.  A marketing plan for developing the property that takes into consideration the compatibility with the Historic District is expected to be advertised in the next couple of months.  There is interest in both the private and public sectors for the property

 

 

COMMUNITY INVOLVEMENT

 

The intense level of community concern engendered by this project necessitated a strong program of community involvement.  PENNDOT benefited from the inputs from three community task groups, two in the preliminary design phase and one in the final design phase.  The Citizens Advisory Committee included 17 members representing residents’ and business interests.  A sub-group called the Community Design Task Force (CDTF) was formed with a larger membership of 22, to focus on aesthetic design issues. 

 

Given the high level of controversy within the community about this project, the CDTF provided a forum for a broad range of citizen interests to build their own consensus about a vision for the community and the contributions possible from the new bridge and access through Factory Street. Their foreword to their guidelines report states in part, that while federally mandated highway design “standards have helped improve highway safety and the efficiency of our transportation network, they have done little to address urban design and social issues in the neighborhoods and communities which highways affect.”

 

The Community Design Task Force (CDTF) sought to educate themselves through assessing the character of the proposed project area and its environs, research on historic and contemporary bridge and tunnel types to better understand the economic and environmental determinants of structure types and structural forms, and photographic studies of Susquehanna River bridges.  The Guidelines publication identifies underlying principles of their work:  Cost and Benefits, Value Added, Design Approach, Urban Character, Riverfront, and Linkages.  Regarding the Design Approach, they asked that the project team, “Give equal consideration to transportation and community design objectives.  Be flexible with the interpretation and application of federal design criteria.  Permit reasonable accommodations in design consistent with the existing scale and urban situation of the project.”

 

The CDTF’s publication, “Community Design Guidelines for Replacement of the Danville-Riverside Bridge” provided valuable guidance to the engineering firms responsible for final design of the bridge and Factory Street connection, allowing them to move ahead quickly with design work with confidence that there would be community support for concepts that adhered to the guidelines.

 

A community Design Group (CDG) of 33 participants with membership overlapping the two previous groups was formed to assist the engineers with final design.  They met 19 times over an 18-month period providing valuable input to expedite the design process.

 

 

NATURAL ENVIRONMENT ISSUES

 

A causeway, necessary for construction of the new bridge and removal of the existing bridge required review and approval by the state’s Department of Environmental Protection (DEP).  Additional restrictions included fluctuating river levels, permitting restrictions to half-width of the normal flow, and a flood control levee around Danville.  Careful planning and execution resulted in a complex, but effective construction sequence.

 

The causeway was first constructed from the Danville side through a temporary breach and closure structure in the levee. A temporary stop-log structure, designed to meet DEP criteria, was constructed to maintain the highest level of flood protection.  After the piers were completed on the Danville side, the causeway materials were excavated, loaded on trucks, and hauled to the opposite end of the causeway where they were deposited and recompacted.  The causeway relocation operation was a continuous movement of causeway materials from one end to the other.  In all, the causeway was relocated four times.

 

 

HUMAN ENVIRONMENT ISSUES

 

Issues of the human environment were paramount in this project, from concerns regarding preservation of National Register properties to concerns for the business environment of downtown Danville once its historic role as the primary artery through town was changed.  Many of these issues were addressed in an expert consultant team’s report.  Recommendations developed through this report were incorporated in the Advisory Council’s MOA and these commitments to support mitigation measures were helpful in allaying public concerns.

 

 

SCHEDULE OF ACTIVITIES

 

 

 

PROJECT OUTCOME AND LESSONS LEARNED

 

The completed project is viewed as a major asset with distinctive quality by the public. Despite significant dissention through an overly long project development process, the public’s goals to preserve valued historic resources and for the new facilities to serve as a source of pride and identity for the boroughs have basically been met.

 

It was a drawback that a consensus was not reached among all stakeholders and the project team on the chosen alternative.  While diverse community involvement techniques allowed the project to go forward with substantial input from the public once the EIS was mandated; some stakeholders, including property owners immediately affected by the project, did not feel that all viable alternatives were fully explored or that their concerns had been adequately heard and taken into account in selecting a final alternative.

 

The aesthetic vision for the project elements was developed and clearly articulated by the 22-member Community Design Task Force.  This group set out to address the opportunities for urban design to enhance the boroughs of Danville and Riverside in the bridge project.  The group’s published guidelines, “Community Design Guidelines for Replacement of the Danville-Riverside Bridge” gave direction to the team preparing final designs as they sought to balance the transportation needs and cost restraints together with the community design vision established in the guidelines. 

 

Although the public was involved in the design of the project from 1991 forward through the CAC, the lack of trust created through traditional avenues for interaction with the public in project stages prior to that date was never fully eliminated.  Immediate neighbors in the project area felt that PENNDOT continued to make decisions “behind closed doors” without full disclosure to the public.

 

PENNDOT’s decision to hire a recognized team of experts in historic preservation and commercial revitalization was helpful in providing an “outside” opinion on the choice of two alternatives and in identifying mitigation measures that would help reinforce the historic character of the community and support the downtown business core as it adjusted to a new pattern of traffic.

 

It might have saved years and considerable money if the project had been scoped as an EIS from the start.  Initial interviews with various stakeholder groups should have given clues to the level of disagreement within the public on both the purpose and need of the project and possible alternative solutions.  Had a more meaningful coordination and outreach effort to a full range of stakeholders taken place early and efforts to reach consensus on both the purpose and need of the project and alternatives, project time might have been considerably shorter and project interactions less contentious.

 

The lessons learned in this project process have helped shape PENNDOT’s evolving pro-active effort to involve stakeholders earlier and more meaningfully in project planning, design and development.   Several publications to assist staff and consultants have been published including an Environmental Impact Statement Handbook in 1993, a Public Involvement Handbook in 1995 and a Needs Study Handbook in 1996.

 

D.1      1904 Parker Through Truss Bridge from Riverside at lower right to Danville.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

D.2      Aerial view of bridge under construction.  Danville is at bottom of photo.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

D.3      Aerial view of bridge under construction.  Danville is at top of photo.  Old bridge connects to Mill Street in Danville.  New bridge will connect to Factory Street.  Note relationship of Factory Street to Continental Boulevard.

 

 

 

 

 

 

 

 

 

 

D.4      Tunnel under construction at Factory Street.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

D.5          New bridge.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

D.6      New bridge

D.7      Photo taken from new bridge toward tunnel under Factory Street.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

D.8      Entering tunnel from new bridge.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

D.9      Tunnel under Factory Street from Continental Boulevard side.

 

 

 

 


D.10    Intersection of Factory Street and Market Street.  Looking toward Continental Boulevard in distance.

 

 

 



 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

D.11      Looking along Market Street.  Tunnel is below concrete brick pavers.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

D.12      Sidewalk along tunnel under Factory Street.  Site of Iles House is at right as you descend the walkway.