Graywater/Aquaponic Innovations

    Current centralized wastewater treatment technologies throughout the US remove roughly 80% of the macronutrients (heavy metals, nitrogen, phosphorus ... etc.) contained in wastewater streams before discharging the 'treated' wastewater into US waterways - streams, rivers, lakes.  One could argue that with greater technology comes greater treatment; however, when considering the energy necessary for current treatment, a more rational argument may point to the amount of wastewater originating from each private residence.  Consider the US EPA estimation of 100 gallons per person per day!

     We began research and development of graywater reuse combined with aquaponics in 2012.  Graywater is defined as wastewater stemming from household sinks, baths, showers, dishwashers, and clothes washers.  Aquaponics refers to a food growing system which utilizes an inhabited fish aquarium for irrigation and fertilization of edible plants.  Our pilot location was a 1920's apartment with twelve foot ceilings.  The concept was to capture wastewater exiting the kitchen sink in a bucket, then hoist the bucket to a high spot where we could slowly drain the bucket into a wetland system and ultimately into the fish tank.  Water from the fish tank, meanwhile, would be pumped up and into a series of grow beds above the tank, slowly draining excess water back into the tank.

The kitchen before system construction

Space within the apartment was extremely limited, thus we began devising a way to utilize vertical space.  With the concept in mind, we installed a 60 gallon fish tank complete with 4 koi.  Fish in aquaponics serve as the "canary in the coal mine" if you will.  If toxins are present in the system, or the pH is off, we will see it first in the health of the fish.  Healthy fish equal a healthy system overall.

Weight bearing ledgers installed

Our first order of business was to fully inspect the proposed area's structural integrity.  After poking around in the ceiling and walls, we were able to confirm that the   building was 'over built' -               structural timber was plentiful       and cheap in 1920s Missoula.  

By placing weight-bearing ledgers perpendicular to wall joists, we would be able to space the weight of the structure across the wall. Once the ledgers were up, it was time to create and install the wetland graywater system.

The wetland graywater system consisted of a series of specialized PVC pipes filled with medium, which would serve as a surface for bacteria and stability for the wetland plants.  Again, unfortunately, I did not think to take photographs as I was building the pipes or, as I like to call them, biofilters.  (The creation of this blog is helping me realize the necessary steps to have more valuable content.)  We utilized three types of biofilters, each having a slight difference in construction, but all having a very similar interior filter design.  By placing a stainless steel insert into the center of a tube, we were able to force the water down one side of the pipe and up the other.  We were able to modify this approach by simply adding a smaller diameter pipe inside the tube, forcing the water to travel down the inside pipe and then back up in the area between the two pipes.  In my opinion, this was the best filter model, as it requires little effort to build and lessens the chance for leakage.  Another model featured a smaller diameter pipe with a U shape; however, this filter proved to be the most troublesome of the bunch -  I'm not sure if it was the diameter difference or just an inappropriate attempt, but several times the pipe leaked.  If I were to set this system up again, I would certainly not include it.  Into each filter we fitted two outlets - a bib, or valve, near the bottom for draining and water sampling; and a barb adapter near the top for overflow.

Biofilters attached to the ledgers

Drain bucket, plants, and lights installed

We knew that we wanted aerobic bacteria so as to the limit unpleasant smells associated with anaerobic decomposition.  For this reason, we placed a large plastic wiffle ball in the bottom of each biofilter.  Inside each wiffle ball, we placed a bubbler and extended an air hose up and out of the biofilter.  While holding this air hose taunt, we filled the biofilter with large rocks, then more porous lava rock, followed by pea gravel. Finally, we planted wild harvested wetland plants in the pea gravel at the top of the tubes.  Once the filters were installed, they were filled with water from the aquarium in order to introduce beneficial bacteria and to feed the wetland plants.  We also added T5 grow lights above the filters to supplement lighting for the plants.

With the filters in place, we added a three-way valve under the sink that allowed us to divert water to a bucket or the sewer. Once the bucket was filled or, once a day, it was moved to the top of the system and allowed to drain into the first filter.   As the wastewater left the bucket, the incoming water displaced biofiltered water up and out of the first tube and into the next by way of the overflow adapter.  This water then displaces water in the next tube and so on until the bucket drains and additional overflow from the final filter enters the fish tank.

Unfortunately, or fortunately, depending on how you look at it, I was beckoned to a new location and the project halted after about 2 months.  We never installed the planter shelves that would support edible plants watered from the fish tank, as I made the decision to move into another house that was attached to a wonderful yard (and thus the food forest was born ... but more on that later). However, I wanted to share this experience with anyone interested as it was a successful means to treat household wastewater and we certainly would have been able to grow food, while decreasing the volume of wastewater leaving the house.  We'll pick this project back up again at some point, whether it be another in-home system or a larger greenhouse demonstration project.  Stay tuned!

The Garlic Patch - no till gardening

Have you ever looked at a patch of weeds and thought, "I'm going to turn this into a garden?" This was the situation we faced when we first rented our community garden.  A local Missoula nonprofit, Garden City Harvest, rents out 15ft by 15ft garden plots at various locations throughout our community.  Garden plots run about $55/year and returning gardeners are given the first opportunity to re-rent their plot.  This is a key factor, for the primary reason, that conscientious farmers improve their soils from one year to the next, adding value and nutrients each consecutive growing season. That being said, our plot was fairly weed ridden when it came into our hands. Some may see this as a curse, but we saw it as a blessing as it meant our plot had laid fallow for at least a season.  By laying fallow with a cover crop of weeds, the soil organic content, and soil structure of our plot was had likely become higher than plots which are tilled twice per year every     year.

          Our first order of business was to remove the unwanted plants. The disciplines of permaculture (Mollison/Lawton/Holmgren/Holzer), natural farming (Fukuoka), and also basic soil texbooks suggest that tilling or plowing a field damages the availability of soil nutrients and soil structure.  When we stir up the soil, we increase the amount of oxygen, which in turn increases microbial activity.  This increased microbial activity and the physical breakup of soil aggregates during tilling leads to the break down of organic matter, which is essential to the water holding and nutrient holding capacity of the soil.  Once the organic matter is gone, microbial activity decreases and microbes begin to die, surrendering their bodily nutrients to the soil strata.  When plants are present, these nutrients can be utilized; however, when plants are not present, many nutrients will wash down and out of the soil strata.  Consider this - by increasing soil organic matter by 1%, we increase soil water holding capacity by 3.7%!

          Bearing this in mind, we utilized soil forks to remove unwanted grasses and weeds, taking care to disrupt the soil as little as possible.  Our main goal at this stage was to remove roots that would continue to grow - i.e., quackgrass rhizome growth.  Once the unwanted plants were removed, we added 2 bags (6 cubic feet) of Happy Frog soil conditioner and rough raked the whole plot.  We then mixed sand and approximately 2000 seeds of various edible species together to help evenly hand-sow our plot.  We chose this planting method in an attempt to out compete and weeds.

Our plot after 9 days

Our plot after ~ 39 days

In what seemed like no time at all, we had a raging garden of edibles. Sunchokes sprang from the ground and reached toward the sky as kale, radish, and mustard took the middle ground.

By late July, our garden was an oasis of green between gardens with neatly rowed crops and paths.  When we visited the plot, we saw little to no weeds.  We noticed weeds encroaching on the sides of the gardens, but very few within the garden itself.  In fact, the few weeds we did see inside the garden were spindly at best, desperately trying to gain hold amongst the edibles.  We made another discovery during this time - the ground was always moist and never dry, even during the hottest of summer days.  Granted, we were fortunate enough to have rented an irrigated plot, but this ran only once per week.  Turns out, having a crowded garden allows for greater soil coverage by plants, thus decreasing the amount of evaporation of soil water to the atmosphere!

 It was fantastic to visit the garden at this point - there was never much 'work' to do, rather, we admired the now flowering edibles, the insects they drew, and of course, the endless bounty of harvest!  During one visit, we harvested about 2/3 of the garden - flowers, tender seed pods, and stems, which in turn became 10 gallons of delicious green kim chi.  The yellow, white, and purple flowers added great aesthetics to the batch!

Our plot after ~ 140 days

By removing 2/3 of the plant matter from the garden, we allowed plants that were struggling with competition to fill in.  While we worried that this would allow for weed growth, we were pleasantly surprised to see tall, lanky kale begin to fill out and take over.  By the end of the growing season, we had about 1/3 of the plot in seed and the rest in purple leaf kale!

Seed harvest with Lia and J.B.

After a successful season, it was time to close the plot for winter. Sunchokes were dug up - some for eating, some for replanting elsewhere - and about 1/2 of the remaining seed stock was harvested.  Harvested seed stock was removed from the stem in complete pods and stored in brown paper bags over winter in a cool dark space.

Next, we employed a weed wacker to make light work of the above ground biomass.  This was raked to the side so that we could assess the plot and prepare for our next planting.


Thus began our garlic patch.  At this point, we made straight rows by pounding a stake into the ground, attaching string and then stretching it straight and securing it to another pounded post.  We were then able to dig a small trench for the garlic. Rows

Removing above ground biomass, while leaving root structure intact

were spaced roughly 12 inches apart and garlic cloves were spaced about 6 inches apart.  The cloves were placed about an inch under the soil surface and the trench filled back in.  Once the garlic was planted, we pulled the removed biomass back onto the plot and spread it around.  We then spread one bale of straw over the entire plot and whalla, the garden was prepared for the winter!

Now I wish we could show you pictures from the following growing season, but alas, no one in our group thought of taking any!?!

Making rows and planting garlic

What I can tell you is this - we visited the plot only a handful of times.  In our visits, we noticed that nearly all of the garlic had sprouted and in the rows between, seeds left over from the successful kale, mustard, and radishes had sprouted. We were again able to out compete the weeds with edibles, even though we used no herbicides and we planted no new seed.  At the end of the season, we counted 480 heads of garlic harvested from our little 15 ft by 15 ft plot!

We closed the plot this past growing season in a way quite

Closed for winter

similar to that noted above, albeit, this season we filled the garlic trenches back up with compost, then raked the soil, then added the biomass and straw.  I'll be sure to add pictures from 2014!

Side note - we will put a crop other than garlic in for 2015, as it is suggested that Alliums should only be planted in the same place for two consecutive years before rotation.  More on that later though!  Happy planting!!!

How warm is a cold frame? and First spinach of the season

A few months ago, I wrote a blog post detailing how to build a cold frame made from recycled materials. In that post, I mentioned that I would test to see how "warm" my cold frame really was, using two temperature probes.  I placed one probe inside the frame, and the other one nearby in the garden.  I put radiation shielding on each probe (aka pvc pipe) to try and measure shade air temperature.  By comparing the diurnal temperature profiles for each prope, I should be able to tell how effective the cold frame is at raising nighttime temperatures.  

Anecdotally, the box is working wonderfully! I just had my first spinach salad from the box, only 24 hours after it snowed 2", and in a neighborhood known for deer and deep morning shade.

After building the frame, sealing up air gaps with soil and leaves, and letting the cold frame thaw the soil, I shallowly cultivated the soil, threw a few handfulls of spinach seed down, and walked away.  I left the frame in my father's garden, and I could only get by a few times a week to check on the seedlings.  I would occasionally prop the lid open, or close it, but it was mostly left propped about 1/3" open all day, to protect from frost in case my father forgot.

It turns out that the cold frame did an excellent job protecting against frost, as I expected.  However, I also learned that despite satisfactory results (greens to eat), I need to do a much better job of opening the box on clear, sunny days.

A summary of my findings:  Out of 30 nights where it got below freezing outside the box, it only froze on 9 nights inside. I just extended my season by 21 days out of the 45 that I ran the experiment.  The coldest it got in the box was 24.7 degrees, which did not kill my spinach.   The maximum frost protection provided was 22 degrees on March 17, when the lid was closed and covered with styrofoam and a rock. It got down to 13 F outside that night, and stayed 35 F inside the box.

Unfortunately, the box also got above 100 F on 13 different days.  Luckily, the spinach, and some lettuce transplants managed to survive these hot conditions, including a scorching 123 degree afternoon at the end of March. 

Stay tuned for more news about our cold frames at the Missoula Co Fairgrounds! We are in the process of construction preparation right now, and they should be up within the month.

If you are really interested....here is all of the data graphically instead of just highs and lows, or contact me for a spreadsheet.

Freedom Gardens: Baby Steps closer to Victory

Our project building cold frames at the Fairgrounds has taken leaps and bounds this week.  Not only have we acquired a key building material (triple-walled polycarbonate), we also finalized our design, staked out the boxes, and became affiliated with a local non-profit (more to come on this topic).   By working with an existing organization, we hope to be able to secure grant funding to expand this project into a full blown demonstration of cold-season food production.  We hope to show that by applying simple, cost effective technologies, we can extend our growing season and increase access to locally grown foods throughout the year.  We also hope to utilize this space to demonstrate other useful technologies including a greenhouse, worm composting bins, and gravity drip irrigation by offering topical short courses to community members.

Freedom Bed #1

Freedom Gardens.  It does not look like much yet, but come May, we will have installed 90 linear feet of raised beds protected by polycarbonate lids, watered entirely by a gravity-fed drip system.  

We decided to lay out our beds to that they would face 30 degrees west of south (210 degrees on a compass).  We did this so that our boxes will capture the maximum amount of mid-afternoon sun in the winter - a crucial time of day to build up heat in the boxes to last the long night.  

After surveying in the box locations, we painted their outline in green.  By the end of the week, the ever helpful Fairgrounds crew will loosen the soil with a grater, and then excavate down 2.5 feet with a front end loader.  After excavating out the soil (a loam full of cobbles), he will back fill it with screened topsoil.

Looking North towards the racetrack

Out of the goodness of their hearts, and a bit of extra top soil, the Fairgrounds crew also constructed us a fabulous berm.  Not only will this berm serve as a privacy fence, we will put our water reservoirs on top of it to provide pressure for the gravity powered drip irrigation system.  The berm runs up to the horse racing track, where FG crew will be able to easily fill up our tanks from the water truck with a hose from this water truck.  The truck holds 3500 gallons, so they should be able to fill up our planned ~1800 gallon reservoir easily.

The polycarbonate.  We decided to use Thermaglass™ brand triple wall polycarbonate, partially because a greenhouse builder down in Darby ordered a crate of it so we could save on shipping. We loaded up four 6’ x 16’ sheets on a boat trailer, and made the slow drive back.  Today, we cut each sheet into four 4’ x 6’ pieces.  Each of these pieces will form the lid for a bed.  Heath and Mark did most of the work cutting the polycarbonate while I took photos.  We used a sheet metal blade on a circular saw to rip it, to reduce the potential for chipping compared to a wood blade. 

Close-up of the polycarbonate

Next steps.  Mark is in the process of drawing up the final designs for the cold frames, and we will be able to put together a list of lumber we will need.  After we draw up this list, we will make a visit to our local re-used building materials center  I'll post the plans when we get them drawn up.

The site should be graded and topfilled this week, and we will be getting soil test results back from the lab soon.  That means we will need to decide on what compost we are amending our beds with, and if we need to do any correction of soil micronutrients.  We still need to figure out exactly how our irrigation system will be laid out, but we plan on using 15 mm drip tape, with 8" spacing between emitters.  Within the next week or two, we will be able to build these suckers, and begin growing from seed and from transplant. . 

Heath and Mark observe tool safety

    And finally, our terribly ferocious mascot, Teddy Chompski:

Building a cold frame with a reclaimed shower door and lumber

The balmy, Pacific Maritime winter that Missoula has been experiencing has made me think about ways that I can grow, or harvest vegetables year round.  There are many basic technologies that gardeners employ to extend their vegetable growing, or harvest season.  Most season extending techniques utilize some sort of protective covering that conserves or traps heat underneath the protection, to raise soil and/or air temperatures. Season extender technologies include low hoop-houses (cloches), high tunnels, row covers, cold frames, and warm frames.  Each of these technologies has its advantages and drawbacks in terms of cost, durability, mobility, and scale.  Cold-frames are low cost, easy to install, and durable.  However, they are less movable than a row cover or cloche, but  are ideal for the home gardener who is planning to use the box year after year.   

Using a cold frame, gardeners will be able to extend the growing season for a few weeks in the spring and fall, and may use a cold frame to store or overwinter crops of carrots, onions, etc. until they are ready for harvest.  A cold frame is essentially a rectangular box, with a glass lid on top. Many gardeners in our lattitude transplant frost sensitive species (cucumbers or pumpkins) into cold frames to give them a leg up in the spring.  Cold frames can also be used to grow cold hardy greens (mustard, spinach, mache, chard, etc.) weeks later in the fall, and weeks earlier in the spring.

I was at my local re-claimed building materials center (www.HomeResource.org), a few weeks

 ago, and saw that they had a couple of dozen tempered glass shower doors sitting in the yard, begging to be used for some project.  Although you may think that the opacity of tempered shower glass might be a less than ideal material for a cold frame, the uneven and frosted glass is excellent at diffusing sunlight, so that all sides of the box receive even light, and to protect plants from harsh, direct sunlight as the season progresses.  Also, this glass is shatter proof, and will be much less prone to damage from a hailstorm, or a lawnmower hitting a rock.  

There are many styles of shower doors available at Home Resource, and I chose two identically sized shower doors (about 5' x 2.5') which already had a full length hinge attached to the door.   I wanted the shower door to be slightly pitched towards one direction (to better collect light from the southern sky), so I purchased reclaimed 2x10 boards for the back edge, and 2x6 boards for the front edge of my cold frame.  The sides were made out of short pieces of 2x10 cut on the bandsaw into trapezoidal shaped wedges.   

Here is a list of supplies I used for 1 cold frame:

Sides and back: 62" + 2*27" = 116" of 2x10 lumber

Front: 62" of 2x6 lumber. 

I planed a 1x4 down to a 1/2" width, and ripped it in half to fit inside the hinge.

4 metal brackets to stabilize inside corners of box (see second photo)

Some 3" deck screws

Former Shower door with full length hinge

I designed the box so that the metal frame around the shower door would lie flush on the wooden frame (ideally).  After cutting the front and back boards to the proper length, I used a table saw with the blade on a 10 degree bevel to cut off the front edge of each board, so that the shower door would sit flat.  

To make the sides into trapezoids, I used 2x10 lumber, drew the pattern on the board, and used a band saw to cut one corner off, to make a trapezoid.  Because I'm not skilled with a bandsaw, I used a planar attachment to get the side boards perfectly straight.  Taking your time getting these pieces right will improve the ultimate air-tightness of the frame. 

I then assembled the box using metal brackets on the inside, to stabilize the shape, and 3" deck screws to join the boards from the end.  After removing the handle and latching mechanism on one side of the shower door, I screwed the door, and hinge onto the box using biting metal screws.  

After assembling, there were still some air gaps so I used self-adhesive rubber foam to fill the gaps, and trimmed them down with a utility knife.

For a total cost of less than $15 dollars, I was able to make a cold frame that should help me grow greens in the spring and fall, and protect frost sensitive plants for years to come!  Look for updates as the season progresses - I'm planning on installing temperature probes to determine how effective the cold frame is!