Most of the city is kept very clean and public restrooms are well maintained.
A great amount of rain falling in a short time caused severe flooding in September of 2013. The rise in groundwater left basements flooded and sewage systems overtaxed; Boulder County was designated a Federal Disaster Areas. Flash floods are sometimes a concern in Boulder, especially with the spring snow runoff. To keep residents safe and healthy, the government of Boulder offers a Community Flood Guide, which provides information on a wide range of flood-related concerns, including drinking water and sewer backups.