Preparing Your Portland Water Feature For Winter

by Ben Bowen

Winter Water Feature FAQ's

Some day in January you will wake up to find ice or (even better) snow covering the ground. Your first thought is "I hope I have some good coffee in the house!" Once you have dodged that bullet another question will smack you in the face:

Should I have winterized the water feature?

This koi pond runs year round.

This koi pond runs year round.

This is a good question, but you should probably answer it before the snow or ice. The answer depends on a few variables. First, where are you located? Second, what kind of water feature do you have?

Location. If you are at a higher elevation you have a higher risk of a damaging freeze. Mt. Scott, Mt. Tabor, Rocky Butte, Forest Heights, the West Hills are all more likely to get a hard sustained freeze. You definitely need to think about preparing your water feature for cold if you live above 500 ft.

Type of water feature. Do you have fish in your water feature? If so, you will not want to turn your pump off for long periods of time. It may be wise to have a pond heater that allows you to keep the pump running. If you do not have fish, then you can feel free to turn the pump off- but should you?

Should I turn off my pond pump in cold weather?

There are two types of pumps: submersible (sits under the water) and centrifugal (sits outside the pond). Submersible pumps can be left running even in very cold weather as long as your pond is not extremely shallow. When a pump is at least a foot under the water it would be very unlikely to freeze in a Portland winter.

Centrifugal pumps sit outside the pond and are more prone to freezing. Most of the time it would be better to leave them running. They generate a lot of heat and running water does not freeze as readily. If you decide to turn your in-line or centrifugal pump off then you will want to drain most of the water out of. If you don't the water that sits in the pump can freeze and crack the pump housing. This is the most common freeze damage we see in Portland.

Will my pond freeze this winter?

When we get sustained cold weather you can get a thick coat of ice on the surface of your pond. As the ice forms, it expands, and pushes against the edges of your pond, skimmer, and bio-fall (if you have one). A concrete pond can crack this way, as can the plastic elements of the pond. The solution? Alleviate the pressure. If you do not have a pond heater, just put a tennis ball in the pond, skimmer, and bio-fall. The ball will take the pressure off the edges of your pond. This simple trick really work!

So, pond owner, you now know what to do to be ready for winter:

  1. Make sure you have a good supply of quality coffee.
  2. Know what type of pump you have.
  3. Determine if you need a pond heater.
  4. Buy some tennis balls.

More About Water Features:

Ross NW Watergardens Builds Water Features

What You Need To Know About Water Features