The Voi Municipal Water Pump House 03 was a GWC Trans-African Pipelines pump house located approximately 17 kilometers from the industrial town of Voi, Kenya, near the UNSC base Crow's Nest. It is a part of the continent-wide pipe system that starts at water purification facilities near Mount Kilimanjaro, and is one of the pump houses responsible for Voi's water supply. The Tsavo Highway runs under the building, and it has a chain-link gate that can be used to close down the highway at that point despite a highway tunnel with heavy gates nearby.
Before the Battle of Earth, there was apparently a maintenance or construction operation in progress in the area, as several pipes had been unearthed. It was a site of an engagement between the UNSC and Covenant forces during the Battle of Voi. During the engagement, Jiralhanae-led Covenant forces engaged several squads of Marines guarding the area, prompting an intervention by John-117 as he advanced on the Artifact. The humans eventually broke the siege and advanced onwards, regaining control of the pump house.