Construction planned in river near Waste Pits

Cross section D of the Bridge shows rebuilt dolphin bumpers at left, and rebuilt fenders and rip-rap (stone) fill in Red color. See Reference plan on page 8.
Cross section D of the Bridge shows rebuilt dolphin bumpers at left, and rebuilt fenders and rip-rap (stone) fill in Red color. See Reference plan on page 8.

TxDOT will rebuild bumpers, column fenders

EAST HARRIS COUNTY — The Texas Department of Transportation (TxDOT) has applied for a permit from the Army Corps of Engineers to reconstruct the bumpers and fenders in the San Jacinto River, to protect the structure of the IH-10 bridge. These structures have been damaged by repeated storms, including Tropical Storm Imelda, and also by barges that hit them as a result of the storms.

In their permit application, TxDOT claims that the construction would not affect any adjacent land, because construction would be entirely from within the river. However, maps show activity quite close to the waste pits. See illustrations enclosed.

PROJECT DESCRIPTION: TxDOT proposes to permanently discharge 0.193 acres of fill material in the form of pilings and rip-rap into 338.4 linear feet (LF) of the San Jacinto River, during replacement of damaged dolphin structures and fender systems.

Plan of construction shows the work area in green, and dolphin bumpers and riprap fill (stone) in red. TxDOT says all construction will be done from barges in the river, and only in the highway right-of-way, not on adjacent land. However, an access road borders the waste pit site.

Four dolphin structures are to be replaced by the proposed project. The existing damaged dolphin structures would be removed by heavy machinery on barges within the River channel and new dolphin structures would be installed in the same locations. Each proposed structure is 30 LF, for a total of 120 LF of impacts. The acreage of each proposed dolphin structure is 0.015 acre, for a total of 0.060 acre of permanent impacts. The fenders of the proposed dolphin structures are 18-inch-diameter steel coated with a marine-grade epoxy coating. It is undetermined if the pile fenders will be braced with either 18-inch to 24-inch-diameter braces and timber railroad ties or plastic lumbers (Concept 1) or braced with 24-inch to 36-inch-diameter bracings with pile fender wraps (Concept 2). Both concepts would include pipe sleeves around the pile and would result in the same amount of permanent impacts to the San Jacinto River.

To repair the navigation fender system, 77 steel pilings would be required. Each piling will be coated with a marine-grade epoxy coating and would measure approximately 1.5 LF, in diameter, and impact 0.00004 acre of the River. Of the 77 fender pilings, 15 pilings would be located within the proposed riprap so the linear feet of impacts are only calculated for 64 pilings as the linear feet of impacts of the 15 pilings within the riprap are included in the riprap linear feet calculations. These pilings would total 96 LF in permanent impacts to 0.003 acre. Approximately 0.130 acre (1,454 cubic yards) of 24- inch stone rip-rap and 3- inch bedding material is to be placed along the proposed east fender, extending for 122.4 LF.

ALSO quoting from the permit application is the impact on adjacent river banks:

All work would be completed within existing right-of-way (ROW). No work is proposed along the banks of the San Jacinto River as the proposed construction techniques would facilitate completion of all work from barges or the bridge structure. No permanent or temporary construction easements are included in the proposed project. The project is considered necessary to increase the safety to ships utilizing the channel and to protect the bridge from impacts.

AVOIDANCE AND MINIMIZATION: The applicant has stated that they have avoided and minimized the environmental impacts by the following construction design techniques:

TxDOT proposes to complete the project via barge or from the bridge structure, thereby avoiding any impacts to the banks of the San Jacinto River or three Section 404 wetlands within the project ROW.