Category Archives: slow sand water filter study and construction

Update; January 17, 2022: As of 2017, rainwater harvesting is legal in Nevada. There are regulations, however. And the use is limited, but it is no longer illegal to harvest rainwater in Nevada. https://water-law.com/can-nevada-gardeners-collect-rainwater/ Update; September 16, 2016:   We have … Continue reading →

Above are the tests on filter 4 after 3 weeks of running, following being frozen solid for the month of January, 2013. The filter has not had enough water running through it to completely restore the active bio-layer. The roof … Continue reading →

A few notes here about backwashing  a small slow sand filter. This mainly applies to DIY (Do It Yourself) filters, with one exception noted below in the next paragraph.  Do not forcefully backwash your DIY slow sand filter. You may very well … Continue reading →

The filters described on this blog and the associated websites have been tested by 2 different EPA certified laboratories: AmTest in Kirkland Washington, and The city of Everett, Washington environmental lab The test results can be found here and here. … Continue reading →

Filter 5 was frozen solid and not running for 2 weeks in January of this year (2013). Before that for 5 days the filter froze at night, and then ran for 6 hours each day. As of Jan 25 the … Continue reading →

All but two of the filters have been frozen solid for 2 weeks (15 days), with the exception of the two filters that purify shallow well water. The water that runs through them has been running continuously and was still … Continue reading →

The filters we work on here in western Washington state have been in operation outdoors through temperatures as low as 15 degrees F (at night) for as long as 1 week, with below freezing (32 degrees F) continuously for 7 … Continue reading →

There are more and more websites and YouTube videos appearing on the internet showing how to “build your own slow sand filter”. Some of the videos have what appear to be very impressive results; but be cautious. The correct functioning of … Continue reading →

The temps have been 28 degrees F at night for the past 4 days now. All the filters have frozen up at night, and thawed out during the day. Last night, Jan 2/3 was the coldest so far, 25 degrees … Continue reading →

Slow sand filters are totally sustainable, will work on gravity feed only, take out hydrocarbons, bacteria, viruses, and do not require addeed chemicals to operate. Check out the websites below. And check out the post just before this one if … Continue reading →