Smart meters provide a more accurate measure of customer water use than previous, mechanical meters. Mechanical meters have been found to run more slowly over time, leading to instances where a customer's water use was underreported and therefore the bill to be low. The City of Allen stopped replacing old meters in 2019 in preparation for the citywide installation of smart water meters. This means meters that may now underreport water use may still be in use, resulting in lower bills that do not accurately reflect the full amount of water used. New meters will register all water consumption so customers are billed for accurate amounts.