Water in our Japanese Garden

SJG 5/19/11 • Kathy Blanchard and photo of Village
Gatehouse by Bob Hoshide; photo by Lynnda

by Lynnda

Yesterday was Unit 86's May continuing education meeting. It was warm and sunny, just a typical May day in our Garden! We welcomed Kathy Blanchard to the meeting since no one knows more about our water system than she does. Before we started our garden tour, Kathy was presented with a lovely framed photograph of the Village Gatehouse in autumn looking south with the kare sansui (dry creek bed) on the left. The photographer is Bob Hoshide who also was the architect for the gatehouse. Kathy still works for Seattle Parks Department but her duties no longer include being head gardener for the Japanese Garden.

SJG 5/19/11 • Moss covered bank of the stream before
it flows into the pond: photo by Lynnda

When the garden was originally built in 1960, the area was a boggy lowland that received runoff from all the surrounding hillsides. Originally, a small pond was present and a stream flowed north into it. In the mid 70's, there was a severe fish kill due to construction contamination from a hillside above the garden. The potential for future spills was realized and a collection system was designed and built to prevent this from happening again. A built water source was also designed using city water. Timers had to be installed so the creek and waterfall would turn off at night, allowing for adequate water pressure for irrigation purposes.

SJG 5/19/11 • Moss-covered banks of the stream before
it flows into the pond; photo by Lynnda

Did you know that the stream and the waterfall have to be tuned? This doesn't happen often, but it requires several gardeners to be at different locations, and adjust various valves to create the perfect pitch. The stream sounds softer than the waterfall, and the waterfall has a gentile and soothing tone. They both have their own source of water, and they are loud enough to provide a soothing mood regardless of the traffic outside the garden.

SJG 5/19/11 • Male Gadwall swimming with  koi;
photo by Lynnda

The pond health is critical to the koi health. The temperature is regulated by adding more water on warm, sunny days. As Kathy explained, the pond has moods and the garden staff can tell by the color, texture and the koi behavior when the stress level needs to be calmed. The murky nature of the water allows for better reflection, also providing mystery. One can't tell how deep the water is, although in most places, it's only 2 or 3 feet deep. There are deeper holes, known mainly by the gardeners and koi.

SJG 5/19/11 • Intricacies of the Japanese Garden pond
filtering system; photo by Lynnda

We had the rare experience of going in and out from the east gate which is no longer in use. We were shown where the storage tanks are (since no one had a confined space license, we didn't actually see them) but we did get to see the filter house. Several City departments work with the filtering system since this is critical to keeping the pond algae-free and odor-free. This type of equipment is usually used in pools or ponds with concrete walls, but the natural pond in the garden presents problems that take a team to resolve.


When walking through the Garden, the stream, waterfall and pond are such central compenents of everyone's experience. The background that Kathy provided enhances my appreciation of how much work goes into keeping it all so natural. Thanks to Kathy for such an informative talk and to all the gardeners who do such a great job at the Seattle Japanese Garden.  =D>