The ornamental design for a waterparkfloat, as shown and described.
FIG. 1 is a front perspective view of the waterpark float.
FIG. 2 is a top view of the waterpark float.
FIG. 3 is a bottom view of the waterpark float.
FIG. 4 is a side view of the waterpark float.
FIG. 5 is another side view of the waterpark float.
FIG. 6 is a front view of the waterpark float; and,
FIG. 7 is rear view of the waterpark float.
The broken-line features of the waterpark float in FIGS. 1-2 and 4-7, and the broken-outlined bottom of the waterpark float in FIG. 3, are included to illustrate environment but form no part of the claimed design.