The Design consists of the features of shape, pattern ornamentation, pattern and configuration of the entire interactive water play stream shown in the drawings. Figure 1 is a perspective view of an interactive water play stream according to our new design;Figure 2 is a top plan view of the interactive water play stream of Figure 1;Figure 3 is an extended view of the interactive water play stream of Figure 1;Figure 4 is a cross sectional view of the interactive water play stream of Figure 1 as taken along the line 4-4 of Figure 2;Figure 5 is a left hand side elevational view of the interactive water play stream of Figure 1; Figure 6 is a right hand side elevational view of the interactive water play stream of Figure 1; Figure 7 is a bottom view of the interactive water play stream of Figure 1; Figure 8 is a first side elevational view of the interactive water play stream of Figure 1; Figure 9 is a second side elevational view of the interactive water play stream of Figure 1; Figure 10 is an enlarged fragmentary view of the first feature of the interactive water play stream of Figure 1;Figure 11 is an enlarged fragmentary view of the second feature of the interactive water play stream of Figure 1 in a closed position;Figure 12 is an enlarged fragmentary view of the second feature of the interactive water play stream of Figure 1 in an open position;Figure 13 is an enlarged fragmentary view of the third feature of the interactive water play stream of Figure 1;Figure 14 is an enlarged fragmentary view of the fourth feature of the interactive water play stream of Figure 1 in a closed position;Figure 15 is an enlarged fragmentary view of the fourth feature of the interactive water play stream of Figure 1 in an open position;Figure 16 is an enlarged fragmentary view of the fifth feature of the interactive water play stream of Figure 1 in a closed position;Figure 17 is an enlarged fragmentary view of the fifth feature of the interactive water play stream of Figure 1 in an open position;Figure 18 is an enlarged fragmentary view of the sixth feature of the interactive water play stream of Figure 1 in a closed position;Figure 19 is an enlarged fragmentary view of the sixth feature of the interactive water play stream of Figure 1 in an open position;Figure 20 is an enlarged fragmentary view of a portion of the interactive water play stream of Figure 1;Figure 21 is an enlarged fragmentary view of the seventh feature of the interactive water play stream of Figure 1 in a closed position;Figure 22 is an enlarged fragmentary view of the seventh feature of the interactive water play stream of Figure 1 in an open position;