Figure 24. Cumulative shoreline change at Vero Beach P.E.P. Reef installation (Stauble, 2002).

710

Stauble and Tabar

P.E.P. Reef zone and a mixed sometimes landward and some-

ft) was also in the seaward direction, due to the large accre-

times seaward movement in the south control zone persisted

tion in the last measuring period. The north control zone

from installation to June 1999 (STAUBLE 2002).

showed a slight landward movement from December 1999 to

Reflecting a large post-storm gain in sand on the subaerial

June 2000. However, the cumulative overall project average

beach, the shoreline over the entire project length moved sea-

(August 1996 to June 2000) was still the largest seaward

ward as of the December 1999 survey. Over the cumulative

movement, measuring 9.7 m (31.7 ft). This cumulative shore-

August 1996 to December 1999 (forty-month) period, the av-

line movement is due to the almost constant seaward move-

erage seaward movement of the MHW shoreline reflected a

ment of the shoreline in this zone for the other periods.

gain in sand on the berm at all profile locations. The cumu-

lative shoreline position landward of the P.E.P. Reef moved

Sediment Volume Response

seaward an average of 6.0 m (19.8 ft), showing the first sea-

ward movement in the shoreline since installation. The

Cumulative volume change over the August 1996 to June

shoreline in the north control zone also averaged a large 10.7

1999 period (characterized the general project response) for

m (35.1 ft) seaward movement and south control zone aver-

the north control zone experienced accretion averaging 45.98

aged a relatively large move of 6.2 m (20.4 ft) seaward.

cu m/m (18.32 cu yd/ft). In the vicinity of the P.E.P. Reef,

volume change showed erosion averaging 7.81 cu m/m

Due to lack of storm activity between December 1999 and

( 3.11 cu yd/ft) length of beach. The south control averaged

June 2000 (over the winter and spring), the shoreline contin-

a loss of 5.95 cu m/m ( 2.37 cu yd/ft).

ued to average an overall seaward movement trend for the

entire project length. Most of the seaward movement this

The volume change analysis comparing the baseline Au-

time was in the south control zone. An average cumulative

gust 1996 survey to the post-storm December 1999 survey

seaward shoreline change of 7.6 m (24.9 ft) was measured

showed the same trends in sand accretion as was measured

over the entire study period from August 1996 to June 2000

in the shoreline seaward movement (Figure 25). In the P.E.P.

in the south control zone. Within the P.E.P. Reef zone, the

Reef zone, the beach volume change experienced accretion of

average overall project cumulative movement of 5.3 m (17.4

11.70 cu m/m (4.66 cu yd/ft). The south control experienced a

Journal of Coastal Research, Vol. 19, No. 3, 2003