Valmiki Ramayana Yuddha Kanda Sarga 22 Shloka 36

तदा then, तत्र there, शल्यपीडिता crevice by the dart, वसुधा earth, ननाद popularly known, तस्मात् therefore, बाणमुखात् by the piercing of the dart, रसातलात् from the underworld, तोयम् water, उत्पपात came out.

At that part of the earth that was creviced by the piercing of the dart, water came out from the underworld.