A water conservation fixture system comprises a handle lock assembly configured for placement on a handle of a fixture and at least one other structure selected from a fixture drain insert trap assembly, a fixture screen and combinations of both. The handle lock assembly comprises a top component and at least one locking arm pivotally attached to the top component, and the locking arm further comprising a locking element for releasably locking with a mating locking element on the top component. The fixture system may be integrated into existing fixture to significantly reduce or control water usage or otherwise convert the fixture to a low-water or no-water fixture without having to replace the current water-based fixture. The fixture system may also be integrated into new fixtures with corresponding mating features to optimize fit and function of the system with the new fixture.