Rainwater Catchment from a High Tunnel for Irrigation Use

This program describes how to build a system to catch, store and reuse the rainwater for irrigation in a high tunnel. Shawn Shouse, ISU Extension and Outreach ag engineer, runs us through the process. The cost of installing rain gutters, rainwater storage tanks, and an electric pump is estimated at $1,200. A solar-powered pumping system will add approximately $700 to that cost.
ISU Extension and Outreach offers the publication, "Rainwater Catchment from a High Tunnel for Irrigation Use" for free PDF download: store.extension.iastate.edu/I...

[@user-hb3nw4ow4n]

Yay! Finally someone who knows how to use “Either” and “Both”. Thank you!

[@martintopp1399]

HI there from NZ. I have watched some good videos on rain water collection for a high tunnel, but this one is in another league. This was the most helpful, informative and comprehensive video I have watched on the subject. I had all my questions answered. The search is over. I know what to do now!

[@ISUExtension]

We are so glad to see that we got to answer all your questions!

[@steveparker4343]

That's one hell of a polytunnel. Makes mine look minuscule but I can use the principles. Nice video

[@johnnielawson]

Brilliantly explained, thank you.

[@HometownGardener]

Very good video. I will incorporate a system like this on my new high tunnel. Thank you for the information.

[@Buckinghamrabbit]

Wow…many people are curious and excited by the idea of rainwater capture systems, but I have generally found that- more traditional irrigation methods are better suited and less headache for most gardener and grower applications…but this is an excellent example of a good time to implement this system! I work with a high tunnel that I have not been able to install a frost free hydrant into- I do have a pump and some barrels, however, so I guess I know what my fall project will be!

[@joanies6778]

Wow.. I had in my mind it would be a good idea to do a rain gutter to catch rainwater for plants, & then I came across your video. I will likely use a dark barrel to avoid the algae issues, & move it inside during the winter to help heat the greenhouse. Glad to see some details here that will help me install mine. Thanks!

[@madpuppy1000]

Very helpful. Thank you for posting.

[@bobnewhart4318]

Great video very informative. The toy bay stop valve was genius

[@drewberrynews3875]

Thank you for the great instruction

[@lucascady4992]

Inflatable ball Stop is Genius!! I love this Video!

[@shawnshouse445]

Thanks! But see also the comment from Bill B on Feb 23 and my reply. A simple overflow hole in the tank may be easier and more appropriate in many cases.

[@jayejaycurry5485]

If the greenhouse is anywhere close to trees, a rain guard cap should be installed on the gutter to keep leaves from clogging the system. That was very interesting. I liked the detail shown in the installation.

[@shawnshouse445]

Good point. We had no trees nearby, but if you did, protection for the gutters would be justified.

[@ISUExtension]

Glad the information was helpful!

[@thelittlefarmersfarm5706]

This is a great idea... Gonna use a scaled down version of this on my 16x10x7 Trampoline tunnel... God Bless Folks

[@sujeevanayanananda9407]

Thanks for uploading this very helpful.

[@healthfullivingify]

Excellent job and video teaching us. Thanks.

[@bigiggmac]

Thank you for your excellent video! This can help a whole lot of people :)

[@reneek8223]

Impressive! Keep it up!! Won't work in my current climate, but this of course deserved an applause 👏

[@dodgygoose3054]

Thank you, you just solved my design issue cheers

[@warrenlc57]

Very nice educational video. Thank you for posting.

[@leonardoenriquez8346]

L Warren are

[@ShevillMathers]

Smart idea-I like it.

[@walterschultz]

Previous experience prompted me to paint our storage cube black, to prevent algae growth. Alternative, which we used in white translucent rain barrels, was the addition of Goldfish. Not only did they consume the algae, they gabbled up the Mosquito larvae!

[@melissapowell1361]

Did you find the goldfish effected water quality due to defecation?

[@lisabevans8107]

​@@melissapowell1361 shouldn't matter if you're using the water for pretty much anything but drinking water.

[@sandersonshomestead6818]

I like this design well done! if the tanks were inside the high tunnel the water would warm up and help keep a average temperature over the night hours

[@shawnshouse445]

Interesting idea. Both you and Concerned Citizen suggested putting the tanks inside. In our case, we didn't think the temperature modulation benefits were worth giving up floor space inside. Having said that, there are some crops that benefit from the temperature modulation of thermal storage mass, which is usually spread throughout the inside of the tunnel. Good idea to contemplate.

[@unionse7en]

yes if you had much more water storage per greenhouse space than shown here.

[@ServiceTrek]

the narrator has a pleasant and clear voice. have you ever thought of getting in the audio book business. i've listened to many and can appreciate.

[@rogercarroll1663]

thanks for a clear, informative video.

[@georgemckenzie2525]

Good research ☺

[@basskadd3694]

Very good design

[@greglahue5690]

While down in Southern New Mexico, I noted they more often than not, they used black colored poly-tanks, for outside water storage . With Summer temps. much higher than those of Nebraska, it seemed that the added heat absorption, being black, would be a negative. But it seems the black has a chemical make up, that slows down the tanks degradation from sunlight, but also the blocking out light, inhibits alga growth. W/O perfect filtration an extremely small bit of alga or other foreign matter, can block drippers or emitters. If there is a concern that the water could be too hot for watering, painting the outside of the black poly tank white, should work. Keep in mind most poly pipes and lines, used in irrigation, that are exposed to sunlight, are black.

[@Stiller.Permaculture]

Great video! Thanks

[@shelly5596]

Very nice.

[@MrNelsonhsieh]

Bird droppings and pesticides are on the roof. The rainwater collected half an hour ago is used to water vegetables, and the rainwater collected half an hour later is used by myself.

[@plantguy902]

Great ideas. Take it one step further and educate yourselves about permaculture implements.. the more functions something has the more it offers to all involved. ✌

[@DagaanGalakticos]

Oh goody, hadn't even considered rain collection off my new GH. Mine is made of cattle panels so I'll have to figure out how to attach the gutters.

[@brianlanning836]

We import produce from all over the world where they fertilize with all kinds of crazy things. And you're worried about bacteria from rainwater getting on the produce? Just wash it before you eat it. Also, you should use a rain barrel that isn't translucent white like that. Light can get in and encourage the growth of algae. This can get into the pipes, pumps, and filters. It's a problem in aquaponics systems. Either get a black tank, or get the translucent tank and paint it a dark color to block the light. You should also put window screen over the top of the rain barrel. The rain water can pass right through the screen. And it will catch leaves or other debris. But most importantly, it will keep mosquitoes out of your rain barrel.

[@JNYC-gb1pp]

I've always thought that rainwater barrel should have a lid and screen to keep out insects and bird poop, but a neighbor said no and that all the stuff in their is good for the plant (kinda like fishtank water). I think he's wrong. Am I wrong?

[@miamited69]

You do need a screen so your tank does not become a mosquito breeding tank.

[@JNYC-gb1pp]

@@miamited69 Thats exactly what I suspected. I know that bird poop can carry some pretty bad bacteria and water my lettuces with that water never sounded like a good idea.

[@miamited69]

@@JNYC-gb1pp I have not been concerned with that, I figure that once it hits the barrels it gets diluted enough. I just don't want the mosquitos breeding and then coming back up the down spout to attack me.

[@shawnshouse445]

@@JNYC-gb1pp The amount of bird droppings falling through the tank opening is likely very small compared to what is on the roof, unless, of course, birds are roosting on the edge of the tank opening. We did observe a small amount of insect contamination in the tanks. I agree that bird droppings and associated bacteria are not a concern for the plants themselves (perhaps even bringing a positive, although insignificant nutrient benefit). But we do not want the bacteria in the water to contact edible portions of produce. This is an avoidable extra risk.

[@sevketselcuk4887]

süper olmuş tebrik ediyorum böyle Türkiyede de yapmak istiyorum

[@thefrub]

Why is this guy's voice so musical

[@jamesgeshay2891]

Very impressive design. I plan on installing 4 high tunnels on my farm. No public water or electricity being a very rural site. Is it possible for you to provide a specific list of the components used for your electric and irrigation pumping system. It appears that it would be perfect for my application. So pleased to have come across your youtube.com video. Fine presentation! Thanks!Jim

[@shawnshouse445]

Glad you found the video informative. To be clear, the system we used to recycle the roof water was adequate for supplemental irrigation (just to make productive use of the water that was collected). It would not be adequate for the sole water supply for the tunnel (I estimate the recycled water met around 40% of the water need with fairly normal rainfall). Much larger storage and power system would be needed for the sole water supply. I'd be happy to share what we used with you, but don't want you to proceed on the assumption that it can be your only water source. If you have no power or water supply at the site, you'll need to plan and develop those resources at a larger scale. It might be better if we talked offline about your situation, or if you referred to a local expert in water supply development. Feel free to contact me at [e-mail]

[@DragonflyArtz1]

You guys ROCK!!! I love this!!! What about purification? You know, from stagnant water? Would an air bubbler be enough? Or does some kind of rotation or spin need to occur?

[@shawnshouse445]

Thanks for the compliment! Good question. If we were feeding something like aquaponics, then aeration could be important. For drip irrigation, the primary concern is sediment/algae/other gunk that could foul emitters. A good, flushable sediment filter is critical when using harvested roof water. As far as stirring the tank, any settling of sediment in the tank before it gets to the filter and irrigation system is probably beneficial. If accumulation gets excessive, the tanks might need occasional flushing. Since this water gets used every few days, it won't be stagnant for very long.

[@DragonflyArtz1]

Good points. Keeping it simple makes for less complications down the road as well. Giving focus to the list in hand! Thank you.

[@jimwest5027]

I covered my tank with black plastic to prevent sunlight from getting in, thus no algae.

[@CavanalK5]

Great video. The presenter sounds so familiar. Like someone from a news show in the past but I can’t place it.

[@mikeguitar9769]

I think this is amazing work, and very well presented. Although, I can't help but think that in order for the methods to be accessible to the common grower, perhaps there are ways that such a system's design might be made simpler and less expensive. Perhaps the gutter water could be routed directly into the drip irrigation, with an overflow feature that is activated when rainfall exceeds some rate limit or total volume. This might reduce or alleviate the need in the system for tanks, pumps and electrical equipment, where much of the system's cost appears to be. Existing designs in rainwater catchment might be utilized for implementing such features as overflow capability.

[@shawnshouse445]

Thanks for the comment, Mike. Advancing technology relies on thoughtful users making continuous improvements, and I'm sure folks will find ways to improve on this system. I'm a fan of cheaper and more simple. Water use without storage would be nice. Drip irrigation in particular may not be well suited to that, because it requires pressure of 8 to 12 psi (pounds per square inch) to make the emitters work uniformly and a fairly low flow rate (around half a gallon per minute per 100 feet of row). Our system had pumps rated for 1.5 to 3 gallons per minute at 45-60 psi maximum (adjusted downward with a pressure regulator). A gentle rain might come at around 0.1 inches per hour (a day-long drizzle). At that rate, half of a 30x96 foot tunnel roof would produce around 1.5 gallons per minute. But often Midwest rains come much faster. A more typical summer rain might come at a rate of 2 inches per hour for a 5-minute period. This rate would produce a flow of around 30 gallons per minute. It is not uncommon for 5-minute rainfall rates to get up to 5 inches per hour, which would be 75 gallons per minute from half our roof. Pressure generated from the gutter level to the ground (4 feet) would be about 1.7 psi. So rainfall directly from the gutter would have too little pressure and much too high flow rate to go directly into drip irrigation. Hence the choice of storage tanks and pumps to serve that use. But if your end use could utilize very low pressure and very high flow rates, then direct use of the gutter water might be possible. More simple design in overflow provision would certainly be possible if you didn't mind modifying the tank itself for the overflow. Honestly I just didn't want to cut holes in our poly tanks. Point well taken on that one. Good observation.

[@user-kr9xi5qc4g]

👍 👍 👍

[@concernedcitizen8481]

I would have put the tanks inside the greenhouse to keep everything from freezing and act as a thermal storage. After painting black.

[@freeman6147]

Bravo! In hindsight, would you do anything differently?

[@diogenesegarden5152]

If bacteria are an issue then I had a bit of an 'outside the box' idea; a couple of silver electrodes, powered from the battery, could be fitted in the tank or into a secondary, smaller ready use tank to produce colloidal silver? I don't know if it would be practicable and drip irrigation is probably more efficient anyway, although it could mean that you could use the rain water to wash the produce. I liked NDD Sceptic's idea of an underground storage tank. If it was excavated beneath the tunnel, probably more appropriate in a hydroponic system (where you are not planting in the ground), then it could be used as a heat sump in the winter months.

[@Gnefitisis]

Why not just attach an inline UV light source for sterilization plus a filter? I would rather not add heavy metals to plants.

[@musictech85]

Bacteria is everywhere. Crops grown outside are covered in shit. If it was a problem, humans wouldn't exist.

[@Horse237]

Catching rain water on all buildings is a good practice for areas like mine with 50 plus inches of rain a year. Better I collect water into tanks rather than let it add to flood waters. I can use the water in the tanks when I get a few days without rain. Crops can drown same as humans and animals.

[@nov51947]

Does using the white tanks cause an algae issue? If so, is there a safe algicide that can be used without affecting the plants?

[@Voorhees1973]

was the water pump and electrical on the same board, for a demo. or would you use it that way?

[@ISUExtension]

Yes, the pumps and switches for the pumps were all mounted on one board for ease of display and packing the pumps away for the winter. It would make more sense from a maintenance and safety point of view to have the switches located farther away from the water lines and pumps just to reduce the possibility of water damage and possible short-circuiting. A good catch and a great comment!

[@marknaylor2080]

My idea was much easier I back filled the trench for the plastic with 20mm gravel and arranged a channel to a buried 200 ltr tank at the lower end. To collect the water a float controlled pump in the tank pumps the water to a larger tank..

[@frenchfryfarmer436]

I will use that idea in my design. 2500 gallon ribbed tank

[@lorip4051]

Very nice presentation. Those outdoor tanks are extremely expensive and I can’t help but to think $3,000 for two tanks is beyond most peoples budgets. Unless I am looking at the wrong types of tanks.

[@shawnshouse445]

I'd have to dig for records, but my recollection is that in 2011 we bought the 500-gallon poly water tanks for around $300 each. 2023 prices look to be around $600 from Midwestern farm supply stores. These are polypropylene water tanks often used for bulk water hauling for things like agricultural spraying. I agree that $3000 for storage would be unappealing. An even cheaper option would be a lined below ground storage, like a fish pond. But protection of water quality could be more challenging.

[@lorip4051]

@@shawnshouse445 Thank you so much for the clarification and information you provided. I truly appreciate it!

[@northernozarkhomestead]

Great video, thank you. What angle did you rip the 2x4s at? I'm hoping to buy some ripped 2x4s rather than buy a very few uses (perhaps only single use) table saw,

[@shawnshouse445]

Two objectives here. First, to try to get a nearly vertical surface for attaching the gutter brackets, and second, to make efficient use of inexpensive 2x4s. About 23 degrees would split a 2x4 (1.5x3.5) in half. But you'll lose a bit off both the width and thickness because of the saw blade thickness. About 25 degrees would leave you with 1.5x3.2" or 21 degrees would leave you with 1.375x3.5" (assuming 0.125" blade width). You could try to measure the angle of your frame members from vertical at the height you plan to install the gutter if you want to be more precise with how you cut the lumber. I figured roughly 23 degrees would get me close enough. (Maybe I should have just answered 23 degrees? But I'm an engineer.)

[@northernozarkhomestead]

@@shawnshouse445 Thank you for the very quick response and insight. Much appreciated.

[@petermueller7407]

Hello, is there a paper or parts list available for the solar-powered pumping system, find that idea brilliant! How long does it run with how much water pumped through it?

[@shawnshouse445]

Peter, the companion bulletin (Rainwater Catchment from a High Tunnel for Irrigation Use) does list the parts we used. Free PDF download at store.extension.iastate.edu/product/13734 We did not track the hours of pumping per week or season. The solar system was designed in an attempt to be able to pump all the harvested water with the solar power collected and stored. The pump we used was a Shurflo model 8000-543-236 (12v., 7.0A, 60 psi max., 1.8 gpm max.) to match our irrigation flow and pressure requirement. With about 1000 gallons of storage, our pump would take 10-12 hours to empty the storage, typically spread over 2-3 days. In our case, we also had an AC pump plumbed to the same system to use as a backup if solar power fell short. In our case, we pumped only what we could harvest as rainwater. We had pressurized well water to meet the balance of the irrigation need. You would estimate your water pumping needs, then size an irrigation system. Then select a pump that would meet your requirements, and a charging system that would provide enough power for the pump. There are good explanations of solar water pumping calculations from solar system providers, or in these bulletins: aces.nmsu.edu/pubs/_circulars/CR670/welcome.html extension.msstate.edu/sites/default/files/publications//p3236.pdf extension.colostate.edu/topic-areas/natural-resources/solar-powered-groundwater-pumping-systems-6-705/

[@bigthunder2860]

You got a very nice greenhouse get some alternators makek make electric windmills

[@MrWookie21]

Did it rain since the installation of the gutters ?

[@shawnshouse445]

Yes, we used the system for multiple seasons.

[@wildoxidizer]

I use rocket mass heater to keep mine warm and I have used two bird bath heaters

[@pamquick9037]

Barley straw is a natural that prevents algae from forming.

[@Skashoon]

Would like to hear/see more about your RMH in your greenhouse. It’s a great idea.

[@nddsceptic1940]

Did ISU not consider ground-works ahead of erecting the tunnel? As a retro-fit this is a great solution, but if the tunnel site is long term then this cannot help but hinder maintenance. On an open site, installing land drains around the poly-tunnel to collect water into tanks below ground saves puncturing the cover and replacement issues, extends rain catchment area, is far less obtrusive, and has the benefits of storing water away from frost in the winter - and below temperatures enjoyed by Legionella in the summer.

[@ISUExtension]

That is a good point. This was addressed briefly in the second paragraph of the companion bulletin (PM 3017) store.extension.iastate.edu/Product/Rainwater-Catchment-from-a-High-Tunnel-for-Irrigation-Use where it says “Unless the high tunnel site is elevated from the surrounding area and/or has drainage tiles installed around the perimeter, water accumulates and creates puddles around the sides of the high tunnel. This can create erosion problems as well as saturated soil on the inside edge of the high tunnel.” Because the focus of the bulletin and video was on construction of a rainwater catchment system and not on construction of high tunnel structures, additional detail on site preparation was not included in these resources. More detail on site selection and preparation for high tunnels is included in the Iowa High Tunnel Fruit and Vegetable Production Manual (PM 2098)store.extension.iastate.edu/Product/Iowa-High-Tunnel-Fruit-and-Vegetable-Production-Manual on page 10

[@tonyanderson5123]

How much did you invest in this project and what is the pay-back time?

[@joshblick]

With all the people that still get their drinking water from cisterns (especially in Iowa), watering plants with rain water is an issue for you? Not to mention how do you keep the rain water from hitting your plants if you have a regular garden???

[@shawnshouse445]

You are right that it isn't the rainwater itself that is a risk. It is the biological contaminants on the tunnel roof that could be washed off by rainwater. Granted, the risk is fairly low, but it is easily minimized by using the captured water for soil level irrigation rather than canopy irrigation. Just passing on what our food safety experts recommend. And almost nobody uses roof-fed cisterns for drinking water supplies anymore, even in Iowa. Certainly if they did, they should include disinfection as part of their water treatment. Thanks for the comment.

[@MrDregNET]

I would recommend to have the water tank inside , cuse the water will be at heat resoware during night time

[@shawnshouse445]

True, the thermal mass of the water could help to level out the day/night temperature swing inside the tunnel. I'm not sure the benefit would justify giving up some interior tunnel space, and it would make an accidental overflow of the storage tank more problematic.

[@testsamiam-my7su]

I could see doing a low tech system using a raised tank and gravity.... or put the water back in as it rains on the roof

[@rprp07110]

Free water!

[@deborahard6780]

Where can I get the plans to build the high tunnel shown in this video?

[@shawnshouse445]

Our high tunnel was a kit purchased from a supplier. Here are a few university bulletins that have lists of suppliers for such equipment. You may have a local supplier you'd rather use. Our lists do not imply endorsement, and omission from our lists does not imply disapproval. u.osu.edu/vegprolab/high-tunnel-suppliers/ blogs.cornell.edu/hightunnels/structures/structure-and-equipment-sources/ extension.msstate.edu/publications/publications/high-tunnel-suppliers If you choose to build your own, here are a few bulletins with advice. extensionpublications.unl.edu/assets/pdf/ec308.pdf pods.dasnr.okstate.edu/docushare/dsweb/Get/Document-9943/HLA-6720web.pdf blogs.cornell.edu/hightunnels/structures/structure-and-equipment-sources/ (note this one has some links to construction plans at the end)

[@chrisrichardson8908]

We're did you buy the gutter system

[@kellinehl4177]

Would it be possible to use the run off after the tanks are full to irrigate trees?? Wondering if it would gravity flow enough to be possible??

[@shawnshouse445]

Yes. Our main objective with the overflow (excess) from the tanks is to get it away from the edge of the tunnel where it would cause excess moisture problems. If you could divert it to a location where the water has value, so much the better! To gravity flow through a pipe or open channel, the combination of pipe or channel size, roughness, and slope, determine the flow rate. Tables are available for sizing drain lines or channels. In our case, assuming a peak 5-minute rainfall intensity of around 7 inches per hour, or using the maximum capacity of our pair of 5" gutters, we would need an overflow outlet capacity of around 0.35 cubic feet per second, or around 160 gallons per minute. In rough terms, that would take a 4 inch tube at 3 percent grade, or 5 inch at half a percent grade, or 6 inch at 1/4 percent grade. Anything down hill that you could reach with those slopes would be possible, if you want to spend the money to divert it more than just letting it run where it wants to go.

[@kellinehl4177]

@@shawnshouse445 Where would I find this said table? Sounds a little over my head but hopefully my husband understands all of that to help me haha!

[@shawnshouse445]

@@kellinehl4177 A couple examples for corrugated plastic drain tubing which you can get at farm supply stores in 10 foot sticks or longer coils, 3 inch diameter or larger: www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs141p2_018127.pdf and engineering.purdue.edu/~abe325/week.10/drainage.htm Both list the flow capacity in cubic feet per second (cfs). One cfs equals 449 gallons per minute.

[@i.mccluskey2835]

Iowa State Extension, where can I purchase a solar panel like that? I am trying to put together some type of solar power to produce enough power to run our greenhouse blower fan and some inside fans.

[@ISUExtension]

The solar panel system that works effectively for us and is easy to install on the high tunnel is manufactured by Powerfilm Solar. www.powerfilmsolar.com/index.cfm They can be found for sale on Amazon.com

[@ISUExtension]

Also, rigid solar panels were used at our demonstration site and they are generally available for a much lower cost for similar capacity compared to the flexible panels mentioned above. Multiple suppliers are available, including Amazon.com, and specialty suppliers such as gogreensolar.com to general merchandisers such as sears.com At today’s prices, solar PV panels can be purchased starting at about $1.50 to $2.00 per watt of rated output.

[@LostCaper]

I suspect this system would stopped the snow from sliding off the green house thus would put a lot of snow load stress on the green house. It's a great idea thou.

[@shawnshouse445]

I agree. Because of the risk of snow and ice on the roof, we removed the gutters during the winter. We were more concerned about snow and ice damaging the gutters. When ice slides off the poly roof, it comes down quickly. The plastic gutter brackets made it easy to unlatch and remove the gutter sections. We left the brackets in place and had no damage to them.

[@shawnshouse445]

Yes, that was a concern, either for snow build-up on the roof, or for snow damage to the gutters. We removed the gutters in winter and reinstalled them in the spring. With the plastic gutters and mounting brackets, that was a simple task.

[@numbereight886]

I'd have assumed that a connection pipe between two tanks below the high water line (at worst) would lead to an equalisation between the tanks.... so the emphasis on absolute level isnt that important

[@numbereight886]

I'd also just have had an overflow pipe on the tank, seems a bit over engineered with ball valves etc.

[@shawnshouse445]

True, the ball valves were a bit complex. I did that so that we didn't have to compromise the tanks with holes for overflow. But overflow holes would be much simpler for an installation where you aren't concerned about possibly re-using the tanks for another purpose. Good point. You'd just have to make sure that the overflow outlet on the tank had flow capacity at least as large as the gutter inlet feeding the tank. You'd also want the overflow to feed back into a drain line of adequate size to handle the flow. I've noticed that rain barrels are often equipped with something like a garden hose for an overflow - much too small to keep up with the gutter feeding the barrel.

[@alph8654]

What about when the plastic needs to be replaced. Tear down the gutter system and do it al over again????

[@shawnshouse445]

Yes, in our case, the gutter mounting brackets were screwed onto the hip board so that they could be removed when the tunnel cover required replacement. We also removed the gutters from the gutter brackets in the winter to avoid damage to the gutters or brackets when ice and snow slide off the roof.

[@GardeningforBeginners]

My tunnel is waves so gutter was not flat

[@Skashoon]

What was the final cost for this project?

[@shawnshouse445]

2011 cost was around $1200 including an electric pump. To use a solar pump instead added around $700.

[@smithrudy8780]

Nice Job. However the float system seems over complicated and unnecessary. Why not jut put an overflow pipe, and direct it where you want the discharge to go? Secondly - the large gap at the tank fill leaves space for squirrels and birds to fall in and get trapped - ruining your water supply.

[@shawnshouse445]

Yes, we had covers over our tank openings, mainly to reduce sunlight damage to the float balls, but they did also reduce the risk of wildlife entry. I like your thinking on that. And yes, I think a simple overflow pipe or opening at the top of the tank would be more simple and cost effective. We considered that, but knew we were likely to repurpose our tanks later and did not want to compromise the integrity of the tanks. But for a permanent installation, I prefer your idea.

[@chrisshepherd2762]

I have found that some inspectors will say there is a safety issue, because the possibility of bird poop being on the roof.

[@shawnshouse445]

Good point. At 8:25 in the video and in the accompanying bulletin we note that harvested roof water will contain bacteria from the dust, droppings and insects that get flushed into the tank. It is important to use it only for soil applied irrigation and not to allow it to come into contact with edible portions of produce, nor to use it for any other purposes. Very similar concerns as for using untreated pond water for irrigation. Thanks for noting that important issue.

[@harddunbye6553]

So How do you keep the birds from shitting on and dust from settling on your plants that aren't in the hoop house?

[@shawnshouse445]

Indeed! You don't. But in this case, we are concentrating things a bit by collecting from a larger area than the plant canopy. The horticulture specialists say that since we are able to put it directly onto the soil surface and avoid contact with edible plant parts, it seems prudent to do so.

[@dorianmccarthy7602]

1:02 .......comprised of?

[@mio.giardino]

There is a gap between the gutter and the brace ropes. The flap attached with tape is not a solution. A cheaper way would be to put a J shaped jig on the plastic that's already there and have it funnel it in to sunken barrels at ether end that has a sump pump in it to send it to an above ground storage tank that can be linked to other tanks via a large diameter overflow hose at the desired water level (no need to have several tanks at the exact same level). Overflow on the 'last' tank can be directed away using the same top of the tank hookup. This way, my way, uses less materials & technology to run. This video is a perfect example how overthinking an idea can waste a lot of resources.

[@shawnshouse445]

Good points. We did lose a small amount of water through leaks around the brace ropes. I did not consider it significant (probably less than 5% loss). On a new tunnel, or replacement top, you may be able to create gutters using extra roof material below the hip board as a trough, and avoid the challenge of getting water off the roof and into the gutter. I thought about that approach, but considered the detachable gutter to be easier to describe and easier for viewers to duplicate. As with most novel projects, once an idea is out there to get people started thinking, farmers will usually come up with better versions that fit their situation and skills even better. Thanks for the ideas.

[@alexcole4970]

how did your suggestions work for you @mio giardino? Your idea on not over thinking seems genius.

[@ami3214]

I appreciate why you put straps over the tunnel. But it will cause more problems. If your plastic is billowing excessively in high winds it’s because it has been poorly installed.

[@426superbee4]

Yes need black tanks are best, unless you used the water fast

[@426superbee4]

screw them plants, put some fiber glass or metal sheet over the green house and i'll move in it. hehehe cheers

[@newbiegardener3980]

why can't rain water be used to water plants directly? I mean isn't bacteria teeny tiny and it would just go through the nozzle any way? drip or hose?

[@shawnshouse445]

Yes, the bacteria would go through the irrigation system. The concern is putting bacteria-contaminated water directly on edible produce. Soil application of the water greatly reduces the risk of bacterial contamination of the produce. Rain water would have much lower risk of bacterial contamination than the harvested roof water.

[@Skashoon]

Rather than a flap, why not simply use the roof repair tape? No need for weights either.

[@shawnshouse445]

Interesting idea to try. I felt the amount of tape needed to use tape alone would have been prohibitive. But could be worth a try, and easy to replace later if you don't like the way it works.

[@lyonscultivars]

Very poor idea that there is no flush fitting to the cover. Most the water flow under and past it

[@asadullah6047]

my eyes....my eyessssss....it's burningggggggggg

[@josephevans5703]

You better get that battery off the ground don't drain it

[@shawnshouse445]

Thanks for the comment. My understanding from battery manufacturer information is that drainage from contact with the ground was a problem with very early lead acid batteries, but since the refinement of plastic battery cases, that is no longer an issue. Check with your battery manufacturer for confirmation.

[@DBCVC]

Amazing the great things one can build with endless funds from the taxpayers!

[@shawnshouse445]

This reply made me laugh. Thanks. Yes, I would consider the cost of rainwater recycling to be hard to justify unless you had no access or very limited access to other water sources. But in some situations, it may make economic sense, and for some operators, it fits other objectives they have beyond economics. For example, in many cases, it may be worthwhile to collect and divert roof water away from the edges of the tunnel even if you don't try to store and recycle it. To be fair, the project was funded by a grant from the Ecology Initiative of the Leopold Center for Sustainable Agriculture.

[@mikeguitar9769]

lol

[@MrDregNET]

Overthinking.. This could bean much more simplified..

[@gominosensei2008]

indeed.... it can be completely un-simplified and not used at all! just collect rainwater in the aquifer and use a well....

[@keith8115]

How many dang times can one person say HIGH TUNNEL.