Before the cold, not during a flood
Plumbing winterization in Aurora
Winterization is prevention. You are draining or protecting lines that will sit in a cold house, a crawl space, or an outdoor faucet. If a pipe has already split, you are on the frozen-pipe page instead.
What people usually mean
Disconnect garden hoses so an outdoor faucet does not stay full. Know where the indoor shutoff is before you need it. Ask a plumber, for a house that will sit empty, which lines they will drain and which fixtures they will leave. A vacant house with the heat off is a different plan from a house you still live in. This guide will not give a valve-by-valve script, because the layout is the house's, not a generic diagram.
Sprinkler systems are often a separate shutoff and a blow-out. Ask whether that is included. An irrigation blow-out uses a compressor and can damage a backflow assembly if it is done on the wrong side. Backflow preventers are drinking-water devices. Do not treat them as a hose bib.
What this is not
It is not a burst that is happening today. It is not a sewer cleaning. It is not a reason to open a gas line. Castle Rock's water utility publishes its own cold-weather notes for customers on Town water, including not operating the street valve. If that is your utility, use their page. Aurora Water's pages used here do not publish a homeowner winterization procedure, so this guide will not invent one and call it Aurora's.
Compare the two jobs on frozen pipe versus winterization before you book the wrong visit.
Questions to settle first
The pipe already burst. Is this the right job?
No. Shut the indoor water if you can do that safely and read the frozen-pipe page. Winterization is the visit before a freeze, or the drain-down of a house that will be empty. It does not repair a split that is already spraying.
Should the plumber blow out the sprinklers too?
Only if the quote says so. Irrigation shutoff and a compressor blow-out are easy to leave off a 'winterize the house' line. Ask whether the backflow assembly on the irrigation is included, and do not run a compressor through a device that is not built for it.
Does Aurora Water publish a winterizing checklist?
Not on the wastewater or service-line pages used for this guide. Do not treat a generic list as the utility's rule. Castle Rock does publish cold-weather notes for its own customers. Match the advice to the utility on the bill.
Do I drain the water heater?
Ask before you do it. Draining a tank that is your only heat source for hot water, or a tank with a closed valve and a flame, is not a casual step. If the house will be empty and unheated, the plumber should say whether the tank stays full, gets drained, or is turned off, and who relights a gas heater later. This site will not give relighting steps.
