The Collaborative International Dictionary of English v.0.48:
Shoaly \Shoal"y\, a. Full of shoals, or shallow places. [1913 Webster] The tossing vessel sailed on shoaly ground. --Dryden. [1913 Webster]WordNet (r) 3.0 (2006):
shoaly adj 1: full of submerged reefs or sandbanks or shoals; "reefy shallows"; "shoaly waters" [syn: reefy, shelfy, shelvy, shoaly]