It depends.

Depends on the relevant terms in the lease, what state you live, how serious the leakage is. I am not in the position to give you any legal opinion. Following is just my understanding of common law regarding landlord-tenant relationship. Read carefully which party, landlord or tenant, is responsible for the certain maintenance and repairs. If it's landlord's responsibility, tenant shall notify landlord the problem relating the leased property. If landlord fails to reponse and make the repair as required by lease, tenant has some options, subject to your residence state. Generally, you can make repair by yourself, and deduct the cost from your next rent. Or notify the landlord you will deduct certain amount from the rent for the necessary repair. The amount withhold or to be deducted shall be reasonable. Again, you shall contact landlord and ask him/her to fix the leakage at rush base. Only after he/she fails to do so, then you can take necessary corrective action as proscribed in the lease and/or state law. Hope it helps and good luck!