An investment in strategic water and wastewater infrastructure has been announced ahead of next week's State Budget.

Development of more than 15,000 new homes across Perth will be unlocked through a program delivered by the Water Corporation to support the creation of more diverse, affordable housing in areas marked for new or higher density development.

Infrastructure will be delivered around METRONET precincts following their completion, including Bennett Springs, Morley and Ballajura on the METRONET Morley-Ellenbrook Line, the future Yanchep Station, and around existing stations at Redcliffe, Meltham and Kelmscott.

Development precincts in Kenwick and Maddington will also benefit from connections to reticulated wastewater infrastructure, with works at Kenwick to commence first.