Former Lambeth Waterworks engine house and pump house (Building No 1)

The former Lambeth Waterworks engine house and pump house, known as Building No. 1, was constructed around 1851-52 by James Simpson for the Lambeth Water Works Company. It is designed in a Romanesque style and was later extended to the northwest.

The building is made of stock brick and features a slate roof. It has an almost symmetrical layout consisting of five sections. The northwest section has a gabled roof with three round-headed windows on the first floor, three blank arches, and double doors on the ground floor. To the left is a two-storey engine house supported by four buttresses, which includes four round-headed windows, cruciform arrow slits, and a round-headed doorcase with colonnettes, accessed by a flight of steps. The adjoining boiler house is two storeys tall but of a lower elevation, featuring twelve square pivoting casements on the first floor, round-headed windows, and a porch with round-headed windows. The section to the left mirrors the engine house's design, also two storeys with buttresses, four round-headed windows, cruciform arrow slits, and large double doors. Finally, the extreme left section is another gabled area with three round-headed windows and five round-headed arches on the ground floor. The internal machinery is from the 20th century.