Toilet Repair in Longmont, CO

Why does my Longmont toilet run if the water is so soft?

Longmont's 2025 water quality report describes the city's water as soft, typically 1 to 2 grains per gallon. It comes from North and South St. Vrain Creeks and Colorado-Big Thompson water, treated at the Wade Gaddis and Nelson Flanders plants and disinfected with chlorine. With so little hardness, the chalky crust that clogs fill valves in hard-water suburbs is uncommon here. When a Longmont tank keeps running, the cause is usually mechanical: a flapper that has warped with age, a chain with too much slack, a float set too high, or a fill valve seal that has simply worn out. Those parts are inexpensive and quick to replace.

What should I expect under the toilet in an older Longmont house?

The city's median home was built in 1991, but about 37% are older than 1980, many of them around the original Main Street grid laid out by the Chicago-Colorado Colony. In those houses the toilet may be on its third or fourth round while the flange and the angle stop are original. If a plumber lifts the bowl to replace a leaking wax ring and finds a corroded or broken flange, that gets repaired before the toilet is reset. Newer neighborhoods such as Prospect New Town are more likely to need only tank parts.

If several drains back up, whose problem is it?

Longmont maintains the sewer mains and will investigate main-line problems, but the city says the sewer service line from the house to the main is owned and maintained by the property owner. If the toilet backs up when the washing machine drains, or the tub and toilet slow down together, the blockage is probably in that private line. After hours, the city directs residents to Longmont Public Safety Dispatch for main-line concerns; a plumber handles the private side.

A local note on permits

Longmont Building Services requires a permit for changes to plumbing systems. Swapping a flapper or fill valve is routine maintenance, while replacing a toilet or moving it may fall under the permit rule, so ask the plumber which applies to your job.