slow sand filter update

The oldest filter here was started in 2007. Its still running. The sand has not been changed since it was started, and it has not been wet harrowed for 9 years. The output water needs to be tested, but the water is clear and looks clean. Still it must be tested. The other filters here are still running and in service. The three pond filters, and four other roof water filters are still running, and producing clear water. All need to be tested again. None have had the sand changed. Three of them have been wet harrowed twice in 5 years, but the sand has not been changed. As I get more time there will be updates. Other concerns have temporarily altered my focus. Now, I hope to get back to more filter work.

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Raw Water: A new health trend?

According to some major news media outlets the latest “fad” is “raw water”.  If one reads the “news headlines” about this issue, it becomes evident that the facts are obfuscated behind the desire to sell news. Reading through the articles does show that this situation is more complicated than just unfiltered bottled water. It appears as though somehow news media outlets have branded unfiltered water as “raw water”:


“Raw water” is such a general term, it is ludicrous. Unfiltered water can have anything in it.  Calling spring water “raw water” and saying it is good to drink because it is “natural” is just as dangerous as believing unfiltered water is ok to drink in any circumstance.

Now, what is “filtered” water? Who filters it and through what, and what, if anything, do they add to it?  What is “raw water”, where does it come from and what is in it?

With filtered water we are supposed to know what’s in it and what’s not in it. It has become apparent lately, that lots of nasty stuff like lead, flouride compounds, and even bacteria can be in “filtered” water. Chlorine compounds are usually added to kill bacteria and fluoride compounds help prevent tooth decay.

Spring water can contain harmful bacteria and chemicals from “natural” sources. It can also be quite pure. The only way to be sure of the condition of a water source is to have the water tested regularly and to know the source and the existence of any possible contamination. Testing water is expensive and complicated. I’ve done it. Its nearly impossible to keep up with.  Drinking unfiltered bottled water means you must trust the bottling company to provide safe water.

Please, lets not confuse water from a spring, or a deep well; with water in a lake, river, stream, or public reservoir, in other words, surface water. Water from any of these sources is in effect “raw” water; that is to say, untreated water. Water from a deep well is exponentially safer than surface water. Both are raw water in that they are untreated, or unfiltered by humans. Spring water and deep well water are usually filtered naturally. Often, water must pass through lots of sand and often compact glacial till, before it is accessible. Some well water is actually water that was trapped deep under ground hundreds, and/or tens of thousands of years ago, when there were no people living to pollute. Surface water is subject to contamination from sources not found in subsurface soil, sand and compact glacial till (limestone like substance).  Anything water comes into contact with on the surface will be present in the lake, stream, river, or reservoir it ends up in. Just about anything from motor oil, to dangerous bacteria or viruses, pesticides, herbicides, toxic metals, fertilizers, paint residue, garbage, petroleum products of any kind; anything people use, make, throw out, discard, burn; can be in surface water. Drinking that water with the intention of getting “good” bacteria is totally insane. Putting well water, and spring water in the same “raw water” category as surface water is equally insane.

As far as selling “raw” water: that is an opportunistic scheme using obfuscated facts in order to make huge profits from selling water. If you want water that won’t make you sick; get distilled water and add the necessary minerals to it. A gallon of distilled water costs about 1 dollar. What is being charged for that special “raw water” that supposedly contains all that beneficial bacteria? Do people selling that “raw water” tell you specifically what “beneficial bacteria” you get when you pay for “raw water”?

Rain water is distilled water. True, there may be some contaminants in it but its not really polluted until it hits a surface. Water is one of the best solvents (if not; the best solvent) known to science.




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Slow sand filter update

It is now November 6, 2017. This summer was unusually hot and dry. Many forest fires in this state. Horrific air pollution from the fires. All electrical connections were disconnected for safety reasons. No recirculation of water through the filters for 4 months. Now the rains have returned and the filters are working in spite of being inactive for 4 months.

It looks like this will be another unusually cold winter. The first snow was this past week. Below freezing temps now at night.  More later.

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Slow sand filter update

It is now April 16, 2017. All the filters are now running again after having been frozen solid this winter.  Hopefully we will have the time and finances to do another water quality test on them. As soon as we have more information, we will post it here. We are in our tenth year of work with slow sand water filtration study.

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Slow sand water filters in freezing weather

This is an update on the condition of the filters running here with respect to the below freezing weather we have had here in Western Washington state the past two months. There was nearly 3 weeks (part of December and part of January) where the temperature only got above freezing for 5 days during the daylight hours. From Dec 30 to Jan 19, the average temperature was 32 deg F.  with a low of 18 deg F.

All the filters froze solid. Pipes were pushed apart where they were not glued. Several connections that were glued were totally destroyed. So far, all of the connections that were not glued have been found to be ok. We are slowly repairing the damaged pipes that were glued. One pressure tank was destroyed. That is in the process of being repaired. All of the damage found so far, could have been prevented with proper maintenance.

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Rain water harvesting regulation

We get lots of political posts here, particularly people complaining about “big government” “trying to control rain water”.

Please, keep in mind,  “we the people” are the “big government” “We” can change laws, peacefully. Secondly, there are no State governments in the U.S. that specifically prohibit rain water harvesting. I’ve done the research and there have been posts here by others documenting the legality of rain water harvesting. That said, if you have credible documentation regarding a state law, or a particular county’s law, or an HOA (Home Owners Association) that specifically prohibits rain water harvesting then please, include a link to the source and the text of the law; and we’ll gladly approve your post. There may very well be HOA’s (Home Owners Associations), and, city and/or county governments that prohibit rain barrels / and or rain water harvesting. If you live in an area like that; get together with your neighbors, and have the county and or city laws changed. If you signed an HOA agreement, you’re just out of luck, you’ll need a good lawyer. An HOA is not “big government”. HOA’s are non-governmental organizations. There are limitations, however, on rain water harvesting. In most cases these limitations are not unreasonable, unless you want to have your own private lake in your back yard. There are darn good reasons for water laws, and there are absolutely ridiculous reasons based only on greed, and/or total ignorance. Obviously, in most cases, having several rain barrels, and perhaps a few 1000 gallons of water properly stored, will have virtually no effect on a neighbor’s access to water.

One of the issues that comes up repeatedly is the idea that: “I can do anything I want to on my property and nobody should be able to stop me”, and if I want to build a small lake, and fill it with rain water that should not be anybody’s business except mine. Another common idea is: “rain belongs to no one and falls from the sky, and if it falls on my property it should all be mine”. In a perfect world, that might be true. This is not a perfect world. Ok, this gets really political. “Regulation” is absolutely necessary, because any thing you do on “your” property will, in one way or another, influence your neighbor. Its all about the extent of influence.

Please, please; if you must rant about the political situation regarding rain water harvesting, and have no credible source to cite, don’t post your opinion here. Find a political blog. There are hundreds of pages on this blog, and the last thing people need to do is search through a bunch of political rants looking for information and documentation on rain water harvesting techniques. 


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Slow sand filter update

It is now January 27 of 2017. Its been cold this past 6 weeks: below freezing for 42 days with only 5 days where the temperature was in the upper 30s during the daytime. The ground remained frozen the entire 42 days. That’s 42 nights of  below freezing temps here, mostly in the lower 20’s. All of the filters, with the exception of filter 3, and 4,  were frozen solid until 5 days ago. Filter 3 and 4 froze up when I forgot to increase the flow at night. Had I kept the flow up they would not have frozen. Filter 3, and 4 are the ones that have continuous flow 24/7 from the use of a small pump that either recirculates water through them or runs water through them from a surface well. When I am able I will check all the filters out to determine the extent of damage, if any, and i will post it here. Most of the pipes were not glued, so they just pushed apart with no damage, but I will need to check more closely as the weather warms up. This has happened before just about every year and the filters just keep on working. This year the cold spell lasted slightly longer.

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How long will a slow sand filter last ?

How long will a slow sand filter “run” before it needs “repair”?

This is a good question. This blog has 8 years of posts documenting the slow sand filters running here. I can say with certainty that the longest running filter here (filter 1) is still fully functional after 8 years of continuous running (with the exception of several weeks each winter when all the filters freeze up and stop running). In filter 1, the sand has not been changed and the filter has not been wet-harrowed; and no sand has been removed or added. Recirculation is used in the summer when little or no rainfall occurs.

The other filters running here have been in continuous service for various lengths of time. Anywhere from 5 years to 8 years. All filters, with the exception of the 5 gallon filters, and the smaller 1/2 gallon filter, are still fully functional and currently in service. The 5 gallon filters were not successful, and we have stopped working with them. The smaller 1/2 gallon filter was never fully tested thoroughly enough to show any success.

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Rain water harvesting in Washington DC

According to one of our contributors, Kristan,  it is legal and encouraged in The District of Columbia to harvest rainwater. (see the most recent comment at the bottom of this page on our blog) They have extensive information on how to manage storm water in the District of Columbia. The link below offers some interesting reading.

Read more about this here.

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Colorado legalizes rain water harvesting

The governor of Colorado has signed into law a bill that allows anyone to collect rainwater from their roof. It is now legal to collect rainwater in Colorado. 

HB 16-1005 is the bill that was signed May 12, 2016.  

More here:

And here:

This is a big change from the past one hundred and fifty years or so. It has been a crime in Colorado set up a rain water harvesting barrel until May 12, 2016. Now it is legal. The times, they are a changin’.

Now I am sure there will be people ranting about something they find bad about this. There will be nit-pickers that will find, and point out, limitations and regulations. No matter, this is still a huge positive change brought about by hard work from everyone involved. Change can and does happen, but it takes a long, long time.

Thanks to Susan, for bringing this to my attention.

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