Methods and systems of providing domestic water service to a commercial/residential building via a water booster pump assembly are disclosed herein. In some embodiments, the water booster pump assembly includes first and second water pipe branch circuits. In some embodiments, each water pipe branch circuit is configured with a backflow preventer and the water pipe branch circuits are fluidly coupled to one another in parallel. In some embodiments, the water pipe branch circuits are further coupled to one another via a crossover branch pipe configured to allow continuous flow through the two backflow preventers. Each water pipe branch circuit may include a pump. The crossover branch allows water to flow through both backflow preventers, even when one pump is inoperative.