Annandale Water Hardness & Quality Report (2026)

Annandale, Virginia, an unincorporated community in Fairfax County — a highly diverse Northern Virginia community adjacent to I-495 (the Capital Beltway), widely known as the 'Koreatown of the Mid-Atlantic' (Annandale has one of the largest Korean-American communities on the East Coast, with numerous Korean restaurants, businesses, and cultural institutions on Little River Turnpike), and a major Fairfax County multicultural community home to significant Vietnamese-American, Ethiopian, Latin American, and Indian-American populations — draws its municipal water supply from Fairfax Water. Water hardness in Annandale measures 196.5 mg/L — classified as hard.

Annandale's hard supply — much harder than nearby Burke (89 mg/L) using the same Fairfax Water source — reflects the Annandale distribution zone's significantly older infrastructure. Annandale developed substantially in the 1940s–1960s as a Northern Virginia postwar suburb, and its distribution infrastructure includes older mains from the 1940s–1960s buildout era. These older Fairfax County mains accumulate very substantial mineral content from the Fairfax Water supply, producing the hard 196.5 mg/L at Annandale — much harder than the Fairfax Water source water.

At 196.5 mg/L, Annandale residents face regular hard water challenges. Monthly descaling with citric acid solution is standard maintenance. Fairfax Water consistently delivers water meeting all Virginia DEQ and EPA Safe Drinking Water Act requirements.