TO WHOM IT MAY CONCERN: The Jacksonville District of the U.S. Army Corps of Engineers (Corps) has received an application for a Department of the Army permit pursuant to Section 404 of the Clean Water Act (33 U.S.C. §1344) as described below:
APPLICANT: Eng. Luis E. Rodríguez
Deputy Executive Director
P.R. Highway and Transportation Authority (PRHTA)
P.O. Box 42007
San Juan, Puerto Rico 00940
WATERWAY AND LOCATION: The project would affect waters of the United States associated with the Guanajibo River. The project site would be located in the immediate vicinity of Bridge #1096, State Road PR-102, Km 36, between the Retiro and Minillas Wards, Municipality of San Germán, Puerto Rico.
Directions to the site are as follows: From San Juan, take Expressway PR-52 (southbound) towards Ponce. In Ponce, take State Road PR-2 (westbound) towards San Germán and continue driving until you reach the PR-2 (Km 180.6)/ PR-102 (Km 39.2) interchange. Take interchange ramp to your right towards PR-102; turn left onto PR-102 and continue driving until reaching Bridge #1096 at Km 36.
APPROXIMATE CENTRAL COORDINATES: Latitude: 18.075748°
Basic: River crossing
Overall: Implement measures to protect Bridge #1096 from erosion/scouring impacts, as to ensure its structural integrity and the safety of its users.
EXISTING CONDITIONS: The proposed project site consists of a section approximately 500 meters long of the Guanajibo River, including a crossing (Bridge #1096) associated with State Road PR-102. The project site is specifically located within a meandering reach of the Guanajibo River where large active point bars are predominant inside the river channel and the riverbed is dominated by cobbles, gravel, and sand. The Cupeyes River discharges into the Guanajibo River about 100 meters downstream of the bridge. Bridge #1096 is a thirteen (13) span reinforced concrete cast-in-place structure built in 1969 that has undergone several repair/protection interventions through the years because of hydraulic issues. The alignment of the bridge relative to the direction of water flow is at a skewed angle. As a result, the flow of water is not perpendicular to the bridge, which creates turbulence that causes erosion and undermines the bridge foundations. This problem has intensified during the past few decades due to the lateral river migration that has affected the north river embankment upstream of the bridge. Lateral migration has increased erosive forces on the north bridge abutment and on the bridge piers. Gabion mattresses were installed in the past at the riverbed under the bridge area and concrete skirts were constructed around the piers to protect them from river erosion. Gabions were also installed along the west river embankment to protect the west bridge abutment, and a grade control structure was installed about 15 meters downstream of the bridge. The gabion mattresses under the bridge structure no longer exist, and the gabions installed at the west embankment as well as the concrete skirts protecting the bridge piers are currently damaged.
PROPOSED WORK: The applicant seeks authorization to discharge dredged and/or fill material into approximately 3.09 acres of waters of the U.S. for the retrofitting and protection of the foundations of Bridge #1096 from erosion and scouring. The proposed project activities would include the construction of reinforced concrete apron walls around the bridge supporting piers (as replacement for existing damaged apron walls that would be demolished as part of this project), and a continuous concrete slab at the riverbed beneath the bridge deck. The concrete slab would measure approximately 485 feet (147.88 meters) long x 61 feet (18.6 meters) wide and would extend from the north bridge abutment to the westernmost pier. Two segments of the concrete slab would be built at a lower level to allow river flow during low flow conditions (low flow concrete channels). Sheet piles would be installed at the upstream and downstream sides of the bridge, which would serve as a formwork to construct the concrete slab. A rock revetment would be placed immediately downstream of the downstream side sheet piles. The proposed project would also include the realignment of a section of the Guanajibo River extending upstream and downstream from the bridge structure. This project component would require cutting/excavating material from the riverbed and banks, as well as filling the northern embankment and sections of the riverbed immediately upstream of the bridge to reconstruct the floodplain and terrace in this area. In addition to the above, the project would include the installation of six rock vanes along the river channel (five would be installed upstream and one downstream of the bridge) to redirect erosive forces towards the center of the channel and protect the embankments and bridge abutments from scouring/erosion. Temporary access roads and berms (to deviate water flow and serve as working platforms) would be built in different areas of the river channel during the different phases of project construction, requiring total temporary fill impacts to approximately 2.44 acres of waters of the U.S. The temporary access roads and berms would consist of gravel/excavated riverbed material and concrete pipes or culverts. The debris resulting from the demolition of existing structures within the river channel and the excavated riverbed/banks material not used in the project construction activities would be temporarily deposited in adjacent upland areas for subsequent disposal at an authorized upland site. Staging areas for this project would be established in uplands. The project would require the use of loaders, excavators, cranes, and sheet piling installation equipment, among others.
AVOIDANCE AND MINIMIZATION INFORMATION – The applicant has provided the following information in support of efforts to avoid and/or minimize impacts to the aquatic environment:
The applicant has explained that due to the severely scoured/undermined conditions of the foundations of Bridge #1096, total avoidance of impacts to the waters of the U.S. is not possible. However, impacts to the waters of the U.S. would be minimized by constructing the proposed concrete slab in a previously impacted area where gabion mattresses had been installed in the past. Impacts to the waters of the U.S. would also be avoided and/or minimized through the removal of all temporary fill material associated with the construction of the temporary access roads and berms/working platforms immediately upon completion of the construction work, and by implementing turbidity/sedimentation control measures during project construction.
COMPENSATORY MITIGATION – The applicant has offered the following compensatory mitigation plan to offset unavoidable functional loss to the aquatic environment:
The applicant has expressed that the proposed realignment of the river channel, combined with the planting of trees in the reconstructed terrace and the installation of rock vanes within the river channel would prevent/reduce future erosion of the northern embankment and would thus improve water quality and the general conditions of the river in the project area; therefore, no mitigation should be required.
CULTURAL RESOURCES: The Federal Highway Administration (FHWA) is the lead federal agency for this proposal. The PRHTA, as delegated representative of the FHWA, completed the required consultation with the P.R. State Historic Preservation Officer (SHPO) for potential project impacts to historic properties, pursuant to Section 106 of the National Historic Preservation Act. As a result of said consultation, via letter dated October 7, 2016, the SHPO expressed their belief that no historic properties would be affected by the proposed project.
ENDANGERED SPECIES: In its role as delegated representative of the FHWA, the PRHTA completed the required consultation with the U.S. Fish and Wildlife (USFWS) for potential impacts of the proposed project on federally protected species, pursuant to Section 7 of the Endangered Species Act. As a result of this consultation, via letter dated February 18, 2016, the USFWS determined that the proposed project would have no effect on any federally protected species or designated critical habitat under their purview.
SECTION 408: The applicant will not require permission under Section 14 of the Rivers and Harbors Act (33 USC 408) because the activity, in whole or in part, would not alter, occupy, or use a Corps Civil Works project.
NOTE: This public notice is being issued based on information furnished by the applicant. This information has not been verified or evaluated to ensure compliance with laws and regulation governing the regulatory program. The jurisdictional line has not been verified by Corps personnel.
AUTHORIZATION FROM OTHER AGENCIES: A Water Quality Certification from the P.R. Department of Natural and Environmental Resources would be required for this project.
COMMENTS regarding the potential authorization of the work proposed should be submitted in writing to the attention of the District Engineer through the Antilles Permits Section, Fund. Ángel Ramos Annex Bldg., Suite 202, 383 F.D. Roosevelt Ave., San Juan, Puerto Rico 00918, within 30 days from the date of this notice.
The decision whether to issue or deny this permit application will be based on the information received from this public notice and the evaluation of the probable impact to the associated waters of the United States. This is based on an analysis of the applicant's avoidance and minimization efforts for the project, as well as the compensatory mitigation proposed.
QUESTIONS concerning this application should be directed to the project manager, Mrs. Deborah J. Cedeño-Maldonado, in writing at the Antilles Permits Section, Fund. Ángel Ramos Annex Bldg., Suite 202, 383 F.D. Roosevelt Ave., San Juan, Puerto Rico 00918; by electronic mail at Deborah.J.Cedeno-Maldonado@usace.army.mil; or, by telephone at (787) 289-7036.
IMPACT ON NATURAL RESOURCES: Coordination with U.S. Fish and Wildlife Service, Environmental Protection Agency (EPA), the National Marine Fisheries Services, and other Federal, State, and local agencies, environmental groups, and concerned citizens generally yields pertinent environmental information that is instrumental in determining the impact the proposed action will have on the natural resources of the area.
EVALUATION: The decision whether to issue a permit will be based on an evaluation of the probable impact including cumulative impacts of the proposed activity on the public interest. That decision will reflect the national concern for both protection and utilization of important resources. The benefits, which reasonably may be expected to accrue from the proposal, must be balanced against its reasonably foreseeable detriments. All factors which may be relevant to the proposal will be considered including cumulative impacts thereof; among these are conservation, economics, esthetics, general environmental concerns, wetlands, historical properties, fish and wildlife values, flood hazards, floodplain values, land use, navigation, shoreline erosion and accretion, recreation, water supply and conservation, water quality, energy needs, safety, food, and fiber production, mineral needs, considerations of property ownership, and in general, the needs and welfare of the people. Evaluation of the impact of the activity on the public interest will also include application of the guidelines promulgated by the Administrator, EPA, under authority of Section 404(b) of the Clean Water Act or the criteria established under authority of Section 102(a) of the Marine Protection Research and Sanctuaries Act of 1972. A permit will be granted unless its issuance is found to be contrary to the public interest.
The U.S. Army Corps of Engineers (Corps) is soliciting comments from the public; Federal, State, and local agencies and officials; Indian Tribes; and other Interested parties in order to consider and evaluate the impacts of this proposed activity. Any comments received will be considered by the Corps to determine whether to issue, modify, condition, or deny a permit for this proposal. To make this determination, comments are used to assess impacts to endangered species, historic properties, water quality, general environmental effects, and the other public interest factors listed above. Comments are also used to determine the need for a public hearing and to determine the overall public interest of the proposed activity.
REQUEST FOR PUBLIC HEARING: Any person may request a public hearing. The request must be submitted in writing to the District Engineer within the designated comment period of the notice and must state the specific reasons for requesting the public hearing.