A local plumbing and electric company has released a map that details the closest public restrooms near Metro stations, which aren’t always reliable options when nature calls.

The folks at Michael & Son say they created the DC Metro Bathroom Map to help people “avoid bathroom-related mishaps.” The online tool shows all of Metro’s stations and overlays them with blue toilets if there’s a bathroom in the vicinity and red toilets if you’re crap out of luck. Plus, the interactive guide has step-by-step directions for getting to the bathrooms.

There’s a five-star rating system for “ease of access” to each facility. In the best scenarios on the map, you don’t have to leave the station to use the restroom. Technically nearly all stations have publicly accessibly restrooms, but you have to ask station managers for access and they are hidden in locked hallways; at the new Silver Line stops, though, the bathrooms are in plain sight (though you still have to ask to use them).

In less than ideal situations, the map marks many stations where the best options are places like grocery stores, restaurants, hotels, memorials, and sandwich shops.

And some of the spots come with catches. For instance, at the Starbucks near U Street Metro, “you may be able to use the restroom without making a purchase if you ask nicely. Otherwise, purchase a small tea for $2.25.”

Riders on the southern end of the Green Line have it worst, according to the map. Out of the six stations from Anacostia to Branch Avenue, Naylor Road is the only one with a nearby restroom—it’s at a seafood restaurant a couple of blocks away.

But a large majority of the stations have public bathrooms within walking distance, even if they aren’t the best in the city.