Rainwater tanks are a common feature of the urban landscape in Australia and globally. In Brisbane, Australia, provision of alternative water in new homes is mandatory and to meet this requirement rainwater tanks are considered an important option. The water savings of rainwater tanks can help defer investments in supply infrastructures. An emerging concern is that there is currently no mechanism in place for making sure that the household rainwater collection systems are maintained and in a good condition. In fact, in many locations, there is growing concern about whether the condition of this asset stock is adequate. The paper presents: a synthesis of required basic water tanks maintenance tasks; a short overview of published literature on householder motivations for maintenance; a synthesis of existing information about the condition of tanks, based on literature; simulation model results identifying the relationship between frequency of inspections and the (stationary) proportion of tanks with different types of problems; and the results of a survey to identify judgements about water tank maintenance in the region by professionals and plumbers. The paper concludes that there is a need for collecting more data and that mechanisms need to be in place to ensure the ongoing condition of tanks.