Dedicating land as Waqf for a certain purpose that prohibits spending the revenues on anything else
The grandfather of a person endowed the revenues of a piece of land for building a well. The Waqf (endowment) was transferred from the grandfather to the father (after the death of the former) and they both left no fortune but this Waqf.
The well is no longer used since artesian water pipes are installed and used everywhere. Is it permissible to dispose of this land as we are in dire need of it?
If the reality is as you have mentioned that the well built from the Waqf money is no longer used, the land itself must remain under Waqf. The revenues of this land should be spent on activities which serve the public utilities for the benefits of the people living around the well. Examples of these activities include establishing a Masjid (mosque), building or renovating an establishment for memorizing Qur'an, helping the poor and needy, etc. Moreover, the poor relatives of the endower are the ones who deserve the aid taken from the land's revenues the most. There is nothing wrong with selling this land if it has small or no benefit, then to spend its value on another property that yields much income, but when the lawful benefit necessitates this and after receiving an approval from the judge of the district. In this case, the revenues of the newly purchased land [or property] should be spent on (Part No. 16; Page No. 137) the charitable activities mentioned above. As for the heirs of the endower, they are not entitled to benefit from this Waqf as it can never be inherited. However, they may take from the revenues [of the Waqf] if they are poor and deserve charity. May Allah grant us success. May peace and blessings of Allah be upon our Prophet Muhammad, his family and Companions!