Related for Pesachim 83:7
לא קשיא הא דנפישי דקוו הא דלא נפישי דלא קוו
but you may not pour [it] out on broken [ground].<span class="x" onmousemove="('comment',' Rashi: Broken ground contains shallows and cavities where the water will gather. Instead of soaking in, and will thereby cause fermentation. Jast.: the place where water poured out would remain stagnant.');"><sup>8</sup></span> While another [Baraitha] taught: You may pour [it] out on broken ground? - There is no difficulty: here it means that it [the water] is abundant, so that it collects;<span class="x" onmousemove="('comment',' Hence it may not be poured out there.');"><sup>9</sup></span>
Tosefta Pesachim
Water that was used by bakers may be poured out in a level place, but it may not be poured out in a place with a downward slope (קטפרוס) because it gathers together and becomes leavened.
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