Stormwater drainage systems (open channels, culverts, conduits, pump stations, etc.) are managed by municipalities, utilities, and departments of transportation (DOTs) to collect rainfall, control storm peak flow, and reduce the risk of flooding during extreme storm events. Effective management of drainage systems is especially critical in the era of climate change and rapid urbanization, when more frequent and more intense than normal floods are expected to occur. Asset management offers an alternative to the crisis management approach to dealing with drainage infrastructure failures in the aftermath of floods. This paper addresses key data issues in stormwater drainage asset management, including defining inventory data requirements, developing practical condition assessment methods that consider both hydraulic capacity and physical conditions of drainage assets, and integrating inventory and condition data and documents in a geographic information system (GIS) framework. The developed GIS framework was applied to the stormwater drainage system in El Paso, Texas. In the short term, this framework can help municipalities, utilities, and DOTs to focus on data that are sufficiently detailed to be useful for asset management but not so demanding of time and resources as to be unaffordable to collect and maintain. The long-term benefits, yet to be proved through testing and implementation, are more cost-effective strategies for preserving and improving drainage systems and for reducing the risk of costly flooding.