Table 32 (Concluded)
Construction and Rehabilitation History
An extension of the north and south jetties was authorized.
1958
The north jetty was extended to 7,000 ft. The crest elevation was
1966
+20 ft mllw, crest width was 30 ft, side slopes were 1:2 above mllw
below mllw. Stone weights, based on 165 pcf, were a mini-
and
mum of 20.5 tons for select class
a minimum of 13.5 tons and an
and a minimum of 5.5 tons and an
average of 17 tons for class
average of tons for class
The work required 80,904 tons of
stone, 274,243 tons of class
select class
stone, 192,612 tons
stone, 116,296 tons of class
stone, and 125,024 tons
of class
of bedding material. Stones used in the armor layer were individ-
ually placed by crane.
The south jetty was extended to 7,600 ft. The crest elevation was
mllw, crest width was 30 ft, and side slopes were 1:2 above
+20
1972
below mllw. Stone weights, based on 170 pcf, were a
mllw and
minimum of 22 tons f o r select class
a minimum of 12 tons and an
and a minimum of 6 tons and an
average of 17 tons for class
average of tons for class
Estimated quantities were
66,500 tons of select class
179,300 tons of class
184,000 tons of class
69,700 tons of class
and 79,500 tons
of bedding material. Stone in the armor layer was individually
placed by crane. The design wave was a breaking wave varying in
height along the jetty from 18.5 to 27
Rehabilitation of the north jetty was authorized.
1976
The outer 500
of the north jetty were repaired. The north jetty
and
was sand sealed by blasting between stations
1978
The small-boat basin was constructed at South Beach, Oregon, in-
cluding two high-tide rubble-mound breakwaters with lengths of 1,800
and 700 ft. The breakwaters were designed for a 3-ft wave and a
ft mllw. Crest elevation was +14 ft mllw
still-water level of
and side slopes of
The work
with a crest width of 10
required an estimated 11,500 cu yd of armor stone, 35,700 cu yd of
core and bedding stone for the breakwaters, plus 2,000 cu yd of
quarry spalls and 3,000 cu yd of gravel bedding for shore protection.
Armor stone weight was between 100 and 1,000 lb, with at least
50 percent of the pieces weighing more than 300
The outer
ft of the north jetty subsided to below water surface
1983
and required major rehabilitation.
The harbor and cross section of the jetties are illustrated in Fig-
1985
repairs are planned at this time. Studies are currently being con-
ducted for major rehabilitation of the north jetty.
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