The protected zone of wells: how many cubits is it?

Adi bin al-Fudayl (may Allah have mercy on him) said: I came to Umar bin Abd al-Aziz (may Allah have mercy on him) and requested permission to dig a well. He said: Write down its enclosure as fifty cubits; it shall not take in the right of any Muslim, nor shall it harm him, and the traveller has the greater right to drink from it.

Muhammad bin Ishaq (may Allah have mercy on him) said: I asked Abu Bakr bin Muhammad bin Amr bin Hazm (may Allah have mercy on him) about the enclosure of a well. He said: In the time of pre-Islamic ignorance it was fifty cubits on its surrounding sides, and between two wells it was one hundred. When the era of Islam came, it was seen that less than that also suffices; so twenty-five cubits was set for each well, fifty cubits for its surroundings.

Amir (may Allah have mercy on him) said: The enclosure (parapet) of a well is forty cubits all together. No one is permitted to take over its space or its water.

Urwah (may Allah have mercy on him) said: For a well dug in the era of Islam, the enclosure is twenty-five cubits; for an old well, fifty cubits; and for a farming well, three hundred cubits.

Al-Zuhri (may Allah have mercy on him) said: It has reached me that the enclosure of a spring is five hundred cubits.

Al-Hasan and al-Sha'bi (may Allah have mercy on them) said: The parapet of a well is forty cubits.

The same is also reported from al-Sha'bi through Jabir; they both (al-Hasan and al-Sha'bi) said: The enclosure of a well is forty cubits.

It is narrated from Sa'id bin al-Musayyib (may Allah have mercy on him) that the Prophet (peace and blessings be upon him) said: "For a well dug in the era of Islam, the parapet is twenty-five cubits, and for an old well, fifty cubits."

Sa'id (may Allah have mercy on him) said: The parapet of a farming well is three hundred cubits.

It is narrated from Bilal bin Yahya al-Absi (may Allah have mercy on him) that the Prophet (peace and blessings be upon him) said: "There is no enclosing except for three things: the enclosure of a well, and the enclosure of people sitting in a gathering." (The third thing is not mentioned here, but it is in other books of hadith, and it is tawl al-faras, meaning the enclosure of the place where a man tethers his horse.)