Guide to Grates

There are a lot of different kinds of sewer drain grates in use in Baltimore, and not all of them are bad! To determine if a grate is bad, you can consult the pictures below, but there is an easy ways to check. I ride on 700C 32mm road tires which are pretty standard for road or hybrid bikes in the city - if you ride on wider tires, you might want to check the grate images instead.

After dismounting your bike, roll the front tire over the grate in the direction of traffic. If the tire falls into the empty space or gets caught, that's a bad grate. If a bike can stand up with a wheel in the grate, it's definitely deadly:

Picture of a silver hybrid bike with its front wheel stuck in a sewer drain grate

Simple, right? But you can't always tell by looking. For instances, this one has channels that go in the wrong direction, but they're short enough that I don't think they're a problem:

A sewer drain grate with plants growing out of it that has channels going left to right in the direction of the curb but with small cross-pieces between them to keep a wheel from getting trapped

This one looks similar, but the channels are just long enough and just wide enough to grab the tire and send you over your handlebars:

A sewer drain grate with channels going parallel to the curb in a dangerous way and also it was full of dirt and leaves that I kicked off before taking the picture.

This one seems fine until you look at the edge farthest from the curb - one big long channel for your wheel to get caught - and it's on the East entrance to Druid Hill Park:

An unusual sewer grate that has narrow metal strips going parallel to the curb but also has angular cross-pieces to keep your wheel from sinking in, except in the part farthest from the curb which makes it a deathtrap

The worst of the worst are these ones - long channels and deep holes:

The worst kind of sewer drain for cyclists: long narrow bars parallel to the curb made by rounded bars

You can also look at the many bad grates on the site for more examples!

Are you a MariaDB expert who understands geographic searches? Want to help? Reach out!