is . Modifications and dates Pool-type fencing added in the late 20th century. Heritage listing As at 2 December 2002, Pymble Reservoirs No. 1 (Covered) and No. 2 (Covered) are two reservoirs of a small group of covered reservoirs. Together they demonstrate the variation and development in construction technology and the high level of engineering skill available to the MWS&DB. The two reservoirs on the Pacific Highway at Pymble form an important group of covered reservoirs, integral with fine examples of valve houses. The valve houses preserve their original valve control gear, which is extremely rare in the SWC system. All covered reservoirs are highly significant within the Sydney system, since all differ in construction technology, design and architectural detailing. All therefore contribute to our understanding of the development of covered reservoirs in NSW. The listing includes both the reservoirs and all associated features, pipework, valves and valve houses to the property boundary. Pymble Reservoirs No. 1 and No. 2 were listed on the New South Wales State Heritage Register on 15 November 2002 having satisfied the following criteria. The place is important in demonstrating the course, or pattern, of cultural or natural history in New South Wales. This reservoirs demonstrate the high level of demand by a populous suburban community. This reservoirs or site demonstrates the amplification in demand due to growing population. The place is important in demonstrating aesthetic characteristics and/or a high degree of creative or technical achievement in New South Wales. The two reservoirs on the Pacific Highway at Pymble form an important group of covered reservoirs, integral with fine examples of valve houses, most of which preserve their original valve control gear. The place has potential to yield information that will contribute to an understanding of the cultural or natural history of New South Wales. This reservoirs demonstrate the broad range of construction techniques and high level of technical expertise available for covered reservoir construction. All covered reservoirs are highly significant within the Sydney Water system, since all differ in construction technology, design and architectural detailing. All therefore contribute to our understanding of the development of covered reservoirs in NSW. The place possesses uncommon, rare or endangered aspects of the cultural or natural history of New South Wales. One of a small group of large covered reservoirs in brick or concrete, each demonstrating differences in construction, design and architectural detailing. See also List of reservoirs