Seattle Mayor Katie Wilson has proposed spending $1.4 million a year to add 10 modular public restrooms in busy parts of the city.

The plan builds on a pilot launched earlier this spring with Throne Labs. Four solar-powered restrooms were installed in Pioneer Square ahead of the World Cup. Users enter by scanning a QR code or using a card distributed by Downtown Seattle Association ambassadors.

Each restroom costs the city about $116,000 annually, including maintenance and regular cleaning by Throne’s support team. Wilson described the pilot as a major success in her budget proposal. More than 30,000 people have used the Pioneer Square units; the median visit lasts two minutes, and users have given them an average cleanliness rating of 4.1 out of 5.

Seattle’s earlier efforts to increase restroom access have faced drug use and vandalism problems. Throne co-founder Jessica Heinzelman said only five people have been restricted from using the pilot restrooms.