Rights of a co-owner of a property

Hi, This is the Issue i am facing any valuable suggestions are needed. We have a House built on our property which is divided among three, My Mother, my aunt and my Uncle. The will has been made clear that all three of them hold equal rights to the house and the uderlying land including the common area. The problem i am facing is both my Uncle and aunt have constructed a Water sump in the common area. Now when i want to construct a third sump in the common area without causing any issue to them, They are not allowing me to do the same. As my mother too holds an equal right to the common area, can i go ahead with the construction of the sump? Do i need to get any court approval or assistance such that neither my uncle nor my aunt cause any issue. ? What is the best way for this ? Thank you