Another interpretation: He made them into a kind of heaps. "They stood up like a wall [ned]" (Exodus 15:8). Just as a flask [nod] is bound shut and lets nothing out and takes nothing in, so was the breath of the Egyptians bound up within them. And for Israel, the sea let out for them sweet water from within the salty water, as it is said, "He brought streams [nozlim] out" (compare Psalms 78:16). "Streams" means nothing other than living water, as in the matter that is said, "a fountain of gardens, a well of living waters" (Song of Songs 4:15), and it is written, "Drink water from your own cistern" (Proverbs 5:15).
Sweet Water Drawn From the Salt Sea for Israel
Yalkut Shimoni on Torah 248:2
דָּבָר אַחֵר עֲשָׂאָן כְּמִין עֲרֵמוֹת. נִצְּבוּ כְּמוֹ נֵד, מַה נֹד צָרוּר וְאֵינוֹ מוֹצִיא וּמַכְנִיס, כָּךְ הָיְתָה נַפְשָׁם צְרוּרָה בָּהֶן בְּיִשְׂרָאֵל, אוֹכְלִין וְשׁוֹתִין וּשְׂמֵחִין וְיָצְאוּ לָהֶם כְּדֵי מַיִם מְתוּקִים מִתּוֹךְ מַיִם מְלוּחִין, שֶׁנֶּאֱמַר "וַיּוֹצִא נוֹזְלִים", אֵין נוֹזְלִים אֶלָּא מַיִם חַיִּים, כָּעִנְיָן שֶׁנֶּאֱמַר (שה"ש ד, טו) "מַעְיַן גַּנִּים בְּאֵר מַיִם חַיִּים", וּכְתִיב (משלי ה, טו) "שְׁתֵה מַיִם מִבּוֹרֶךָ".