Responsa for Eruvin 176:6

ת"ש חצר שאין בה ד' אמות על ד' אמות אין שופכין לתוכה מים בשבת בשלמא לרבה ניחא אלא לר' זירא קשיא

view, explained: This refers to an exedra that ran along all the courtyard.<span class="x" onmousemove="('comment',' If, for instance, the courtyard area was four cubits by two the exedra also was four by two, its length being parallel to that of the courtyard and thus extending the area of the latter to four cubits by four.');">¹³</span> Come and hear: If the area of a courtyard was less than four cubits by four cubits no water may be poured out into it on the Sabbath. Now according to Rabbah this ruling is quite satisfactory;<span class="x" onmousemove="('comment',' Because a courtyard that was narrower than four cubits, though longer, is unsuitable for spraying.');">¹⁴</span>

Teshuvot Maharam