Wa `alaykum As-Salamu wa Rahmatullahi wa Barakatuh.
In the Name of Allah, Most Gracious, Most Merciful.
All praise and thanks are due to Allah, and peace and blessings be upon His Messenger.
In this fatwa:
Polluting water, in all forms, is prohibited and contradicts the teachings of the Shari`ah.
Answering your question, the General Iftaa’ Department in Jordan, states the following:
Water is considered one of the greatest graces that Allah has bestowed upon human beings and made it the main source of life on earth, since Allah, the Most Exalted, said: “We made from water every living thing.” (Al-Anbiyaa’ 21:30], and He said: “And We send down from the sky rain charted with blessing, and We produce therewith gardens and Grain for harvests And tall (and stately) palm-trees, with shoots of fruit-stalks, piled one over another.” (Qaf 50:9-10)
Allah created this universe and subjected to mankind everything in the heavens and on earth and made him a vicegerent in it, since He said: “And He has subjected to you, as from Him, all that is in the heavens and on earth” (Al-Jathiyah 45:13]
Therefore, a human being must use the resources that Allah, the Almighty, subjected to him in the best manner and preserve them since they belong to all humans and not only for a certain generation or era. Therefore, none has the right to waste or spoil these resources.
The Islamic Shari`ah legislated specific rulings pertaining to water preservation and urged Muslims not to waste or pollute it, since it is a vital source of life.
Moreover, Islam prohibited polluting and wasting water; rather, the prohibition degree increases if the pollution reached all water resources. Besides, this ruling is in line with the Shari`ah purposes, since the Prophet (peace be upon him) said: “There is no injury nor return of injury.” (Ibn Majah)
In addition, polluting water is considered a mischief on earth which Allah forbade, and threatened the one who commits such an act with the severest punishments, since Allah, said: “So eat and drink of the sustenance provided by God, and do no evil nor mischief on the (face of the) earth.” (Al-Baqarah 2:60) He also said: “But if anyone, after God’s favour has come to him, substitutes (something else), God is strict in punishment.” (Al-Baqarah 2:211)
Furthermore, polluting water resources is considered an act of aggression against all people, because they are partners in this vital source of life, since the Prophet (peace be upon him) said: “People are partners in three things: Water, grass of pasture and fire.” (Abu Dawud)
Another evidence on the prohibition of polluting water is what was narrated from Jabir that the Messenger of Allah (peace be upon him) forbade urinating into standing water.” (Muslim), since urinating into standing water will not only pollute water but it will also harm all people.
In addition, the Prophet (peace be upon him) said: “None of you should take a bath in stagnant water when he is sexually impure” (Muslim), since this will also pollute water and people will no longer benefit from it.
Likewise, the Prophet (peace be upon him) ordered us to preserve water from pollution, so he said:” Cover the vessels and tie the waterskin.” (Muslim)
In conclusion, polluting water, in all forms, is prohibited and contradicts the teachings of the Shari`ah since water in our region is so scarce. In addition, the prohibition degree becomes more dense if this act would lead to the destruction of the environment; for example, throwing industrial wastes and pesticides into springs and rivers, throwing solid wastes, releasing waste water into groundwater, or deliberate poisoning of water to kill harmful animals which will lead to high pollution levels, causing damage to the soil, crops, all forms of life, certain health risks and total loss of water resources.
Almighty Allah knows best.