Date(s) 
Table 2 
Port Bolivar Dike 
Port Bolivar, Texas 
Construction and Rehabilitation History 
1933- 
1934 
1936- 
1937 
1966 
1985 
A 1,700-ft-long steel sheet-pile dike was constructed to prevent 
shoaling in the Gulf Intracoastal Waterway at this location (Fig- 
ure 3). The seaward end of the dike consisted of a 12-ft-diam sheet- 
pile cell, with a 2-ft-thick concrete cap (and underlying fill 
material), protected by a stone blanket at the toe of the cell. The 
top elevation of the sheet pile was +4 ft mlt. Existing water depths 
varied from -4 (landward) to -13 (seaward) ft mlt. A total of 47,500 
sq ft of sheet pile and 6,670 tons of stone was used. Cost of the 
improvements was $25,000. 
The landward end of the dike was repaired and extended 200 ft ata 
cost of $7,050. Approximately 230 tons of stone was placed as scour 
protection at the seaward end at a cost of $1,750. 
The outer 1,230 lin ft of sheet pile was supplemented with a rubble- 
mound section similar to the 1964-1965 Port O'Connor repairs. The 
dike was generally intact, with some damage to the piling at the 
outer end and a heavy coating of rust scale due to saltwater ex- 
posure. Existing ground elevations varied from -5 ft mlt near the 
seaward end to +4 ft mlt along the unrepaired landward segment (in 
general, an accretion of 6 to 8 ft had occurred since original 
construction). The outer sheet-pile cell, with a maximum water depth 
of -11 ft mlt, was the only section where localized scour was evident 
(but in this case not critical to structural integrity). The sheet- 
pile top elevation was generally from +3.5 to +4 ft mlt (within 
0.5 ft of the design elevation). The rubble-mound design sections 
(Figure 3, inset), with the existing dike at the center line, had a 
crown elevation varying from +4 (seaward) to +6 (landward) ft mlt, a 
crown width of approximately 8 ft (2 cover stones wide) and 1V:2H 
side slopes. The sections were built upon a 2-ft-thick (3 ft at 
outer end) bedding layer of 0.5-in. to 200-lb stone. The bedding 
layer extended from 3 ft (landward) to 10 ft (seaward) beyond the toe 
of the cover layer and was covered with a 2-ft-thick layer of 200- to 
1,000-lb apron stone. Similar sized stone were used as core stone, 
and the outer layer consisted of 1- to 6-ton stone. Filler stone 
(0.5 to 4 in.) also were placed with the core stone, in a section 
extending beneath the crown at 1V:1H side slopes. The general pur- 
pose of filler stone is to decrease permeability and reduce sediment 
transport through the structure. The cover stone size was selected 
based partly on Hudson's slope stability equation and partly for 
economic reasons. A total of 19,280 tons of stone was placed at a 
cost of $164,700. 
The dike presently is considered to be in good condition. 
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