Water Channels. Large Channel to East of Great Drain. Round Terracotta Pipe and Settling Basin at Northeast Corner of South Wing of Stoa. Round Terracotta Pipe and Settling Basin at Northeast Corner of ... Η'-12 2259, 2260 S 313 S 314 S 339 ... Round Terracotta Pipe and Settling Basin at Northeast Corner of South Wing of Stoa ... Round Terracotta Pipe and Settling Basin at Northeast Corner of South Wing of Stoa (Demolition) ... Early Stone Water Basin Below East Front of Stoa