Standing water is a five-star breeding ground for mosquitoes, including the species that carry West Nile virus, dengue, and Zika. Furthermore, if the overflow is from a combined sewer system (carrying sewage), the water contains E. coli , hepatitis A, and other pathogens. Children splashing through puddles or pets drinking from them are at direct risk.

It starts subtly: a small, dark ring around the metal grille on your morning walk. By the afternoon, it has become a murky mirror reflecting the grey sky. By evening, it is a stagnant pool lapping at the curb, forcing pedestrians to leap onto the road or hold their breath as they pass.

So the next time you see that murky pool spreading across the asphalt, don’t just step over it. See it for what it is: a warning. A sign that the complex, hidden machinery that keeps our cities clean is under duress. And unless we—citizens, plumbers, and politicians alike—start paying attention, the next tide might rise all the way to our front doors.