Gullywasher White Paper – Biochar


It is always amazing how much is not known about filter-grade biochar, as well as the amount of misinformation about the product. So here is a quick rundown…oak treeBiochar is typically sourced from high-carbon fly ash from wood-fired power plants located at lumber mills and other wood product operations. For filter grade quality for stormwater processes, one needs to be selective on what type of wood is being burnt at that facility. Different types of wood will produce different performances.

Plus it is generally, but not always, best to seek out older power plant processes as opposed to ones recently installed, for their fly ash consists of larger particulates. Not all biochar media are equalThe newer power plants typically produce a powder style of fly ash of which will choke off filter areas. The age and/or the type of the power plant will produce different performances.

To maintain adequate flow rates, filter-grade biochar must first be thoroughly rinsed before it can be used in stormwater applications. Some biochar companies sell biochar from older facilities that utilize a wet fly-ash separation method. The biochar in these facilities enters a water bath and then falls over a weir.

Sometimes this type of biochar is sold as a “washed” product, which is completely false and far from the truth. This “washed” biochar will be loaded by fines and clays, either from the mill’s staging / loading areas or from the power plant burning processes. The initial water bath does not separate these filter contaminants out of the product.

While thorough washing and rinsing is time-consuming and expensive; it is absolutely critical for achieving a filter-grade quality of biochar.detailThe next step in processing biochar is to grade the biochar into a variety of sizes by sequential screening and sieving. Here is some of the alchemy needed to measure how much media permeability is needed versus how much exposed contact areas are available within the media. When selecting the best particle size mixture, there is often a tradeoff between permeability and contact time:

    • The more exposed contact areas provide more intimacy with the stormwater contaminants; hence more contaminants are removed.
    • The smaller the size, the more exposed contact areas within the biochar, the increased resistance to flow permeability.
    • Whereas, the larger biochar particles will allow for greater flow permeability. The larger the size, the less resistance to flow permeability, the less intimacy (therefore less removal).

As you can see, there needs to be a balance with both intimacy and permeability depending on the structure of the filter design.

    • Typically with our biochar filters, we can utilize a granular-sized media if there is a small amount of head available to carry the stormwater through the media, as typical with our upflow and downflow biofilters.
    • However with the lateral flow patterns in our Blue Filter Gabions, the biochar needs to be sized larger in a flake-style which will allow for greater flow permeability.

Filter grade biochar requires certain organic additives in order to achieve a long activation life prior to the media beds being exhausted. A small portion of certain organic acids will activate within the biochar’s alkaline nature, thus increasing bed life and robust removal of metals. In addition, by having aerobic microbes naturally feed on the biochar during the non-rainy seasons; the microbes will expose more exchange sites for metals removal.

We here at Gullywasher strive to offer the best of what a filter-grade biochar can offer within our organic stormwater filter processes require to maximize metals removal, flow permeability, and bed life sustainability.

StormCon Brings New Technology to Stormwater Filtration

National Stormwater Tradeshow, StormCon, Was Successful

brosPortland, Oregon August 3-7, 2014 – It was the BIG SHOW for stormwater management, compliance, and purification. Lots of seminars on many important stormwater topics, coupled with a large tradeshow. Gullywasher was there with two booths which saw a lot of action over the three tradeshow days.

Yes, the Pettey Boys were there in matching twin shirts, just to confuse who is who. They have been doing that all their life since they are identical twins.

winnerWe want to thank everyone who participated in our drawing of four Katadyn Hiker Pro water microfilters. Since Gullywasher specializes in filtering stormwater, the giveaway prizes followed the same philosophy of filtering streams or lake water. There were some broken hearts to those who didn’t get picked.

Promoting their metal-compliance products, Gullywasher has a different type of filtering method, using a passive, easy to maintain, common-sense approach toward purifying stormwater back into compliance.

Their Blue Gabion Filters (BGF) allows local sourced, organic filter media to be used so purifying stormwater can be maximized for turbidity, metals, nutrients, and oils. It is a low-maintenance solution that can be serviced by anyone who is locally available. boothConsiderably less-expensive than the other methods, the BGF is a stormwater filter that was getting noticed at StormCon.

For stormwater drain inserts, Gullywasher’s method of being metal compliant utilizes both basket and framed designs to be easy-to-service with one person, most efficient with using a sodium exchange, and fitting most common sized drains. They put simple into having local talent installing and servicing their storm drain inserts.

For any questions or quotes
on Gullywasher products,
please contact Jeff Pettey
at (260) 799-3296


Out of Sight. Out of Mind.

Ever walk by a piece of litter and tell yourself, "That’s not my trash, not my problem?" It is the same thought pattern when it comes to stormwater pollution. Only it is worse.

stenciling volunteerBecause stormwater pollution goes underground, there is a perception that the problem goes somewhere else. That stormwater doesn’t get treated. It doesn’t get filtered. It doesn’t magically get better. The pollution goes straight into our oceans, our rivers, our lakes, and our ground water.

Of course, that is someone else’s problem. We can see this train of thought in practice everyday.

  • Watching a state convention center employee saying that the hydraulic leak under a forklift as well as the goo coming from the trash collection bins are someone else’s problem while watching the pollution leak into the stormwater drain.

  • Hearing about a German printed circuit board facility dumping 2,000 gallons of cupric chloride into the storm sewer because they did not want to pay to have their toxics handled offsite. They actually had the treatment process and capacity to adequately treat this solution at their wastewater recovery facility.

  • Watching city park employees replace a rusting galvanized dock ladder with another new galvanized ladder. “We got over 50 years use out of this one.” The city spent significant resources upgrading the shoreline for a better salmon habitat just around the corner… "We are only here to replace the ladder. Stormwater pollution is another department’s problem."

  • Watching rainfall push an oil slick from leaking drums on an open parking lot and toward a catch basin while the employee is sweeping in a different area of the same parking lot.

beach cleanupThere is a growing conscience about stormwater pollution, but it needs everyone to participate. It starts with you and me.

Here is one of my easy solutions. The next time you are on a beach vacation, bring along a heavy-duty trash bag. While walking on the beach, just start picking up the plastic, metal, and glass debris. The locals you pass will wave and smile at you. Other people will collect stuff and ask if they can deposit in your bag. Give the collected trash to a beach hotel staff and watch them look at you in awe. You will be considered an honored guest of that area’s beach culture.

Read this related story about Coastal Cleanup Day in San Diego County.

Discussion: The Blue Filter Gabions are filling an important niche in the industrial stormwater market.

The regulators, the non-profits, the technical community, and the industrial end users all want stormwater compliance to be green, cost effective, simple to maintain, and dependable for maintaining compliance.  However until now, there was no effective way of using local, organic filter materials within a simple filter housing that can be expanded and/or configured easily to meet that particular site’s requirements. The Blue Filter Gabions are much like a Lego construct.  With their multiple internal compartments, the consultant and end user can decide which local filter media will do best for their specific application.  Typically compost is used as clarification, removing out the bulk contaminates.  Then a polishing filter media, such as biochar or vulcanized peat moss, will polish filter any residuals.  One of the many nice designs of the Blue Filter Gabion is that whatever potential of having metal leakage from the compost will be completely addressed by the polishing media prior to discharge. Twice yearly, one will need to open up the gabions and top off the filter medias with new local organics.  Or schedule a vac truck to pull whichever media compartment and rebed entirely.  Typically the used filter media will pass the toxics testing and be allowed for use as landscape materials. The first user after the beta sites at Blue Heron Paper Mill is a large electronics manufacturer located in the Portland Metro area.  Its nationally known environmental consultant made the recommendation to place a Blue Filter Gabion into an existing water quality control vault (4’x 4’ x 5’ tall) as a pilot test to see what the capability of this technology is.  Waiting for the next rain event for sampling…

Welcome to the Gullywasher blog.

rain garden

Industrial Rain Garden

We take a common-sense approach in making stormwater compliance simple, inexpensive, and easy to maintain. It’s called the Gullywasher method.

It is plain to see that there are too many people, using too many resources, and causing pressure on our natural habitats – soil, water, air. The municipal, industrial, and construction activities are being pushed to step up and protect the stormwater being shed off their property. Suspended solids, oils & greases, metals, and nutrients are all being monitored and reduced down to near atomic levels in some cases. And it is going to get tighter – as we have to make room for more and more people.