I've previously talked about the kind of collection efficiencies that rain barrel users can expect. They are typically dismal unless you have a very large barrel or the right kind of rainfall pattern. Collection efficiency depends on the rainfall pattern since one large storm would overwhelm most storage systems, thereby wasting the majority of the rainfall whereas a large number of small storms might never once overflow a typical barrel system. In the latter case efficiency would be 100%.
Based on typical southern California rainfall patterns I estimate a typical rain barrel collection efficiency at 10-20%. This is based on my previous analysis after throwing out the highest and lowest rainfall years and applying a factor of two reduction in efficiency, since the numbers I calculated were best case, and nobody is that diligent. Susan Carpenter of the LA Times spent $500 on two rain barrels and received a third for free. If the roof area she captured rain from was 1500 sq ft, then her cost per square foot would be $0.33 for 10-20% efficiency. She was happy to pay it, and I guess that speaks to the psychological impact of having a seemingly large amount of water deposited, as if by magic, in your barrel.
But is 100% efficiency achievable and cost effective? Yes, just about.
2010-11-06
Madrona Marsh demonstration garden
The native plant demonstration garden around the Madrona Marsh visitor center is open whether or not the Marsh is open. While visiting, I met a Torrance city employee and another couple members of the public who were enjoying the gardens.
One reason I had for going was that I had previously identified a small grove of Salix exigua (Narrow-leafed Willow) as particularly pleasing. They had reminded me of bamboo glades in both form and height and I thought them quite elegant. The grove is now closer to a thicket - I think some thinning would be required to maintain the bamboo look over the years but perhaps the look is also dependent upon the growth cycle. I still think it's a pleasing shrub, below at a distance.
Other plants had their autumn finery on:
Erigonum
'Rogers Red' grape identified in the sign as Vitus californica. However we now know that is not true. DNA analysis tells us that 'Rogers Red' is a first generation cross between Alicante Bouschet, a less widely known Vitus vinafera grape used traditionally as a vin de tincture in winemaking and our native Vitus Still looks great!
Catalina silver lace looked luminous.
This plant struck my fancy because of the jaunty dried stalks, though I don't know its name.
Finally, Ceanothus 'Dark Star' - the same that recently died in my yard - shows that branch dieback is more typical than one might suspect.
- Posted at great expense from my iPhone
One reason I had for going was that I had previously identified a small grove of Salix exigua (Narrow-leafed Willow) as particularly pleasing. They had reminded me of bamboo glades in both form and height and I thought them quite elegant. The grove is now closer to a thicket - I think some thinning would be required to maintain the bamboo look over the years but perhaps the look is also dependent upon the growth cycle. I still think it's a pleasing shrub, below at a distance.
Other plants had their autumn finery on:
Erigonum
'Rogers Red' grape identified in the sign as Vitus californica. However we now know that is not true. DNA analysis tells us that 'Rogers Red' is a first generation cross between Alicante Bouschet, a less widely known Vitus vinafera grape used traditionally as a vin de tincture in winemaking and our native Vitus Still looks great!
Catalina silver lace looked luminous.
This plant struck my fancy because of the jaunty dried stalks, though I don't know its name.
Finally, Ceanothus 'Dark Star' - the same that recently died in my yard - shows that branch dieback is more typical than one might suspect.
- Posted at great expense from my iPhone
2010-11-03
Magical rain barrel psychology
In earlier posts I first exposed the cult of the rain barrel as a marginally efficient sop to green guilt but then had an Ah Ha moment in the second post when I related the prevailing theory of how unengaged people will become engaged people through the magic of rain barrels.
The magical rain barrel theory says that Flo and Joe Sixpack will suddenly throw off years of disengagement and disregard for the environment after receiving a free rain barrel from the City of LA(1) After work Joe will park his 4WD full sized truck in the lot-length driveway of their 50's era SFR, amble over to the rain barrel, and switch on the irrigation for his organic free-range tomatoes. He'll share the tomatoes down at the local VFW Hall and, over cold Budweiser, tell the story of the enabling technology of the rain barrel. In doing so he will spread the true gospel. It'll be viral!
FAT CHANCE.
This theory only works on people that are already on the cusp of wanting to do something green. Among LA's west side population I'll take a guess that fraction is at most 5% of households. So if you want to make inroads in 5% of households, go ahead and give out free rain barrels. Heck, I'll take one, though even on my somewhat capacious lot I don't know where I would conveniently keep it. On second thought, cancel my rain barrel. Just send me a crew of workers for a weekend to redo the drainage in my yard to more effectively infiltrate water on site.
What sorts of efficiencies push people's buttons and get them excited and engaged? Hardnosed reporter Susan Carpenter, the Realist/Idealist of LA Times was so thrilled with her $500 investment in 3 rain barrels that she put it at number three on her top list of green innovations. She lived with them for the past two to three years and based on my guess that her roof was larger than 600 square feet, she was probably getting rainwater collection efficiencies no better than I cite in my first blog post - 20% to 47% (her roof is larger but her total barrel size is larger too so these numbers are educated guesses for sake of discussion). But because no one is as efficient as the hypothetical water stud in that post, let's assume Susan had an actual 10% to 24% efficiency out of her rain barrels. She says that it lasted her a month into summer.
And she got excited! So here's a person with green tendencies, presumably somewhat skeptical (she is a Realist, after all) getting excited over an outlay of $500 that netted one less month of watering their fruit trees in summer.
I guess magic does happen.
1. "The City of Los Angeles, Department of Public Works, Bureau of Sanitation, Watershed Protection Division (Stormwater Program) rolled out the City’s first free Rainwater Harvesting pilot program in July 2009.
Residents that sign up for the program will be eligible for complimentary installations of (1) rain barrels (2) downspout disconnections, or (3) custom-made planter boxes for businesses. The captured rainwater will then be either routed to pervious surfaces or used for on-site irrigation."
The magical rain barrel theory says that Flo and Joe Sixpack will suddenly throw off years of disengagement and disregard for the environment after receiving a free rain barrel from the City of LA(1) After work Joe will park his 4WD full sized truck in the lot-length driveway of their 50's era SFR, amble over to the rain barrel, and switch on the irrigation for his organic free-range tomatoes. He'll share the tomatoes down at the local VFW Hall and, over cold Budweiser, tell the story of the enabling technology of the rain barrel. In doing so he will spread the true gospel. It'll be viral!
FAT CHANCE.
This theory only works on people that are already on the cusp of wanting to do something green. Among LA's west side population I'll take a guess that fraction is at most 5% of households. So if you want to make inroads in 5% of households, go ahead and give out free rain barrels. Heck, I'll take one, though even on my somewhat capacious lot I don't know where I would conveniently keep it. On second thought, cancel my rain barrel. Just send me a crew of workers for a weekend to redo the drainage in my yard to more effectively infiltrate water on site.
What sorts of efficiencies push people's buttons and get them excited and engaged? Hardnosed reporter Susan Carpenter, the Realist/Idealist of LA Times was so thrilled with her $500 investment in 3 rain barrels that she put it at number three on her top list of green innovations. She lived with them for the past two to three years and based on my guess that her roof was larger than 600 square feet, she was probably getting rainwater collection efficiencies no better than I cite in my first blog post - 20% to 47% (her roof is larger but her total barrel size is larger too so these numbers are educated guesses for sake of discussion). But because no one is as efficient as the hypothetical water stud in that post, let's assume Susan had an actual 10% to 24% efficiency out of her rain barrels. She says that it lasted her a month into summer.
And she got excited! So here's a person with green tendencies, presumably somewhat skeptical (she is a Realist, after all) getting excited over an outlay of $500 that netted one less month of watering their fruit trees in summer.
I guess magic does happen.
1. "The City of Los Angeles, Department of Public Works, Bureau of Sanitation, Watershed Protection Division (Stormwater Program) rolled out the City’s first free Rainwater Harvesting pilot program in July 2009.
Residents that sign up for the program will be eligible for complimentary installations of (1) rain barrels (2) downspout disconnections, or (3) custom-made planter boxes for businesses. The captured rainwater will then be either routed to pervious surfaces or used for on-site irrigation."
2010-11-01
OFG Hands On Workshop event wrapup
Last Saturday I went to the Hands on Workshop (HOW) that I had heard about through my Ocean Friendly Gardens class participation (see Ocean friendly garden landscaping class wrapup) The workshop covered implementing a site evaluation using a worksheet to calculate current water use, runoff, and a water budget for conversion of a Torrance single family residence to an Ocean Friendly Garden that uses rain water. My goal was to check and cement the knowledge that I gained since I started to install my own native plant garden. I know that I made a lot of decisions based on less data than I could have had and when I build the next garden I want to have a bit more basis for my decisions. I was also interested assessing in the community interest OFGs.
The next step at this residence will be to incorporate the ideas into the Garden Assistance Program Workday (GAP) on Friday, November 26, 10am-4pm. This household is participating in the Garden Assistance Program whereby successful applicants get assistance to have their gardens reworked into ocean friendly gardens. I believe they are paying for plant materials and garden supplies, but the labor and design advice are provided at no cost. The homeowners were very gracious and welcoming (particularly considering that we were tracking mud all over their yard) and provided a light lunch with some delicious homemade berry and guava preserves.
The cost of the HOW, attended by perhaps 40 or more people, was free to the attendees though in the past charges have been up to $25 per person. This underwriting was provided by the City of Torrance since this is the first well-publicized garden conversion in the City of Torrance, who also plan similar garden conversions at several public sites around the city in an effort to reduce water use and provide demonstration gardens.
A (the?) top Torrance water manager was there and stated that Torrance will be moving to more recharge and use of local aquifers and to a four tier water rate system where the top rate will be more than twice the lowest rate, making gardens like this one a possibly significant contributor to the local water economy. It's interesting that no one ever mentions rationing at these meetings without first and more prominently mentioning tiered rates. I figure that aggressive tiered rates is the standard public answer to "what about rationing" types of questions. I hope that it is sufficient because no one is actually talking about real water rationing in California, such as would result immediately from significant infrastructure failure in northern California, or gradually due to continued severe drought. I've not heard of emergency water tiering, whereas emergency water rationing has a more familiar ring. At the class, West Basin Water District representative Carol Kwan related how rationing worked when she lived in Hong Kong: Water was turned on for 4 hours every three days! During the time water was on they filled every pot in the house with water to last through the next three days!
The workshop was useful, the instructors friendly and approachable, and the participants seemed engaged. I'm judging the community interest high based on the number of participants. I also felt particularly rewarded to get the straight skinny in regards to clarifying my mystification at the cult of the rain barrel. I did a little practical garden work, digging a hole to assess soil compaction (over 30 minutes to drain means it's compacted), learned that you only need to remediate soil to the depth of your largest plant (about 12" for 1 gal plants (soil flora and fauna will do the rest), and assessed drainage, learned to identify fungal hyphae and did some figgerin' on soil type and exposure for use in evapotraspiration calculations.
The next step at this residence will be to incorporate the ideas into the Garden Assistance Program Workday (GAP) on Friday, November 26, 10am-4pm. This household is participating in the Garden Assistance Program whereby successful applicants get assistance to have their gardens reworked into ocean friendly gardens. I believe they are paying for plant materials and garden supplies, but the labor and design advice are provided at no cost. The homeowners were very gracious and welcoming (particularly considering that we were tracking mud all over their yard) and provided a light lunch with some delicious homemade berry and guava preserves.
The cost of the HOW, attended by perhaps 40 or more people, was free to the attendees though in the past charges have been up to $25 per person. This underwriting was provided by the City of Torrance since this is the first well-publicized garden conversion in the City of Torrance, who also plan similar garden conversions at several public sites around the city in an effort to reduce water use and provide demonstration gardens.
A (the?) top Torrance water manager was there and stated that Torrance will be moving to more recharge and use of local aquifers and to a four tier water rate system where the top rate will be more than twice the lowest rate, making gardens like this one a possibly significant contributor to the local water economy. It's interesting that no one ever mentions rationing at these meetings without first and more prominently mentioning tiered rates. I figure that aggressive tiered rates is the standard public answer to "what about rationing" types of questions. I hope that it is sufficient because no one is actually talking about real water rationing in California, such as would result immediately from significant infrastructure failure in northern California, or gradually due to continued severe drought. I've not heard of emergency water tiering, whereas emergency water rationing has a more familiar ring. At the class, West Basin Water District representative Carol Kwan related how rationing worked when she lived in Hong Kong: Water was turned on for 4 hours every three days! During the time water was on they filled every pot in the house with water to last through the next three days!
The workshop was useful, the instructors friendly and approachable, and the participants seemed engaged. I'm judging the community interest high based on the number of participants. I also felt particularly rewarded to get the straight skinny in regards to clarifying my mystification at the cult of the rain barrel. I did a little practical garden work, digging a hole to assess soil compaction (over 30 minutes to drain means it's compacted), learned that you only need to remediate soil to the depth of your largest plant (about 12" for 1 gal plants (soil flora and fauna will do the rest), and assessed drainage, learned to identify fungal hyphae and did some figgerin' on soil type and exposure for use in evapotraspiration calculations.
Walking in LA
I came across Where the Sidewalk Starts blog today and found it an interesting read. I have to confess that I was searching for the straight skinny on how I (as a motorist) need to yield to pedestrians. I found that information in a post titled "A Confession A primer on the finer details of crosswalk law."
2010-10-30
Rain barrels redux or Why I can now live in the same world as rain barrels
In a previous post I calculated some optimum efficicencies for rain barrels in sizes of 55 gallons and 110 gallons in support of my feeling that I don't really care for rain barrels. After I had calculated their efficiencies I still wasn't convinced they were a good idea. Today I had the opportunity to ask a garden professional about rain storage and rain barrels when I attended an Ocean Friendly Gardens Hands On Workshop. More on the HOW later, since I know you are all so interested in this garden professional's opinion on rain barrels.
She said, "Rain barrels are the gateway drug to an ocean friendly garden", as near as I can recall. Just as I already knew, just as I already calculated, and just as the workshop today taught, soil is the preferred method of water catchment. But for those who live in blissful ignorance of their impact on downstream flow, rainbarrels raise awareness in an effective way. The rain barrel owners get engaged and that engagement leads to even more effective changes on their properties. Oh, and if you have a vegetable garden or some area that needs a bit more water like fruit trees then by all means use a rain barrel if it meets your space and aesthetic requirements, They do after all provide soft water for free (ignoring the initial costs). But don't look to even a couple 55 gallon barrels as your primary line of defense in a water wise garden.
That was the gist of the insight that I received today, which was well worth the price of admission (several hours of my time plus I learned a few other things). Ahhh...Finally, a rational thought on rain barrels. Given all the hype, I was losing hope that it was out there, but was.
She said, "Rain barrels are the gateway drug to an ocean friendly garden", as near as I can recall. Just as I already knew, just as I already calculated, and just as the workshop today taught, soil is the preferred method of water catchment. But for those who live in blissful ignorance of their impact on downstream flow, rainbarrels raise awareness in an effective way. The rain barrel owners get engaged and that engagement leads to even more effective changes on their properties. Oh, and if you have a vegetable garden or some area that needs a bit more water like fruit trees then by all means use a rain barrel if it meets your space and aesthetic requirements, They do after all provide soft water for free (ignoring the initial costs). But don't look to even a couple 55 gallon barrels as your primary line of defense in a water wise garden.
That was the gist of the insight that I received today, which was well worth the price of admission (several hours of my time plus I learned a few other things). Ahhh...Finally, a rational thought on rain barrels. Given all the hype, I was losing hope that it was out there, but was.
Rain 0.30"; season total 1.93"
We had a nice early morning rainfall that left us with 0.30" of rain. My downspout diverters, which I have been using for years in lieu of a rain barrel to cache water in my garden, worked flawlessly.
2010-10-29
Why I don't think rain barrels are a good idea
You are a rainwater stud or studette! You are such a rainwater stud that you operate your rain barrel in a way that any time there's a day of rainfall you have an empty barrel ready to capture your roof runoff. You feel proud because this is a highly efficient way to manage your rain water. In fact, it's nearly the most efficient way to use your rain barrel. You're so good that even if we have several consecutive days of rain you manage to have an empty rain barrel at the start of each day. I don't know how you do it, but this is what makes you the rainwater stud. At the end of the wet season, how many gallons of runoff have you saved?
I'll try to answer this question and others as I dig into rain barrels in an effort to convince myself that they are a good idea.
There's good instructions on the web for sizing and building rainwater catchment systems. The more comprehensive ones have disclaimers such as, "However, rainwater harvesting for landscape irrigation may only be practical in locations where rainwater can be collected in sufficient quantities during the time that it is needed," which I pulled from the linked web page (from Texas).
Susan Carpenter, the Realist Idealist of the LA Times ranks her three rain barrels third on a list of good eco-innovations - right behind gray water and solar photovoltaic panels and ahead of earthworks (passive garden design to capture rainwater), the Australian waterwall (a narrow rectangular rain barrel that looks like a wall), edible landscapes, and composting toilets. See Composting toilets, backyard chickens and waterwalls: Susan Carpenter's eco-living experiment
She spent $500 ($300 for two rain barrels (a third was free from the city) and $200 for installation and parts) and writes of the rain barrel experiment,
I was a rain barrel skeptic before I joined L.A.'s rainwater harvesting pilot program last fall.... Though rainwater holds such enormous potential for supplementing Southern California's dwindling reserves of imported water, rain barrels seem like such thimbles. During a normal L.A. winter, my 1,500-square-foot roof generates 13,500 gallons of water — a tidal wave compared to what a little barrel can handle.
Which is my concern exactly, but I don't think that under most circumstances that it's best mitigated by her next observations:
Having lived with rain barrels for a year, I've learned that their small size makes them manageable and affordable. The water they catch isn't stored only for summer use. It can be drained in between rains to water nearby plants. An added perk: reducing storm-water runoff to the ocean.
...The 175 gallons they hold were a lot more useful than I'd expected for feeding my exceptionally thirsty fruit plants. The water they held lasted about a month into the summer.
Under certain circumstances (for instance, your roof drains to unavoidable hardscape and then directly off property) I can see a benefit of rain barrels, but for the vast majority of suburban homes I can't see the ecological benefit over garden infiltration. There will almost NEVER be a cost savings if Ms. Carpenter's costs are typical: $500 for three unsightly barrels?
Let's try to put some numbers to my misgivings.
Let's assume that you, the rainwater stud, have 600 square feet of roof (half of a modest sized suburban home's roof area) and a 55 gallon rain barrel. Then it would take about 0.15" of rainfall to fill the barrel (using a conversion of 231 cu. in. per gallon). That means that after 0.15" of rainfall any additional rain is not captured!
Looking over the last six years of rainfall information in my own LA-area backyard (One of my not so private obsessions is rainfall statistics. I'm using my daily records of rainfall to make the tables below. You can do the same thing with a modicum of effort, an Excel spreadsheet, and the daily rainfall tallies for your area. Note to Steve Libby: Naturally I predicted the statistical utility of this data years ago when I started recording rainfall :-)
I'm also assuming I made no mistakes with the analysis, something that has not always proven to be the case, but the numbers seem to be what I expected and time is growing short so with an arrogant tip of my nose I'll take the "meets my expectation" observation as confirmation that they are indeed correct. Most of LA and a wide area of coastal southern California should be similar to what I present below. In fact, the inclusion of our driest year (06-07) and our wettest year (04-05) probably bounds the calculation for most of southern California: you should have results no worse and no better than predicted in those years.
Finally, with caveats and rambling prose out of the way, I can make the assessment of the impact that a rain barrel would have had on the rainwater stud's runoff, had he or she sited it in my backyard in any of the preceding six years:
There are two cases below. They use identical rainfall patterns (that of my back yard for the given years) and identical roof area (600 square feet). They differ in the size of the rain barrel. [Note that the number of down spouts doesn't matter. I assume ALL the rain from a 600 sq ft roof goes into the barrel or barrels. I'm writing this parenthetical note in response to a comment I received elsewhere suggesting that I add downspouts.] The upper table gives values for a 55 gallon rain barrel and the lower gives values for a 110 gallon rain barrel. In our recent wettest year, 2004-05, a 55 gallon rain barrel would only have been 11% efficient at capturing rainfall but would have been 65% efficient in our driest year (2006-07). For the case of the 110 gallon rain barrel the numbers are 19% and 99%, respectively. Average efficiencies are 0.47 for 110 gallon rain barrels and 0.29 for 55 gallon rain barrels.
I have to admit that the efficiencies are surprisingly high, particularly with larger capacity barrels. However, our assumptions tell us that our rainwater stud isn't always using the water when it's most needed in the garden, which is between storms. Instead, over consecutive storm days that exceed capacity the barrel has to be drained to get the kind of efficiencies that you see here: you actually would have to water with your barrel while it was raining in many cases. Consider also, that 600 sq ft of roof is only half of a small 50's era SFR roof. For larger homes the runoff will increase in proportion to the roof area driving efficiencies down for the two cases set forth above. I'll leave this post as it is now, with a high likelihood of a return visit to this topic later when I can stand to think about this again.
More locally-relevant information about rain barrels is contained in a fairly thorough document that does not address rain barrel efficiency at www.larainwaterharvesting.org.
I'll try to answer this question and others as I dig into rain barrels in an effort to convince myself that they are a good idea.
There's good instructions on the web for sizing and building rainwater catchment systems. The more comprehensive ones have disclaimers such as, "However, rainwater harvesting for landscape irrigation may only be practical in locations where rainwater can be collected in sufficient quantities during the time that it is needed," which I pulled from the linked web page (from Texas).
Susan Carpenter, the Realist Idealist of the LA Times ranks her three rain barrels third on a list of good eco-innovations - right behind gray water and solar photovoltaic panels and ahead of earthworks (passive garden design to capture rainwater), the Australian waterwall (a narrow rectangular rain barrel that looks like a wall), edible landscapes, and composting toilets. See Composting toilets, backyard chickens and waterwalls: Susan Carpenter's eco-living experiment
She spent $500 ($300 for two rain barrels (a third was free from the city) and $200 for installation and parts) and writes of the rain barrel experiment,
I was a rain barrel skeptic before I joined L.A.'s rainwater harvesting pilot program last fall.... Though rainwater holds such enormous potential for supplementing Southern California's dwindling reserves of imported water, rain barrels seem like such thimbles. During a normal L.A. winter, my 1,500-square-foot roof generates 13,500 gallons of water — a tidal wave compared to what a little barrel can handle.
Which is my concern exactly, but I don't think that under most circumstances that it's best mitigated by her next observations:
Having lived with rain barrels for a year, I've learned that their small size makes them manageable and affordable. The water they catch isn't stored only for summer use. It can be drained in between rains to water nearby plants. An added perk: reducing storm-water runoff to the ocean.
...The 175 gallons they hold were a lot more useful than I'd expected for feeding my exceptionally thirsty fruit plants. The water they held lasted about a month into the summer.
Under certain circumstances (for instance, your roof drains to unavoidable hardscape and then directly off property) I can see a benefit of rain barrels, but for the vast majority of suburban homes I can't see the ecological benefit over garden infiltration. There will almost NEVER be a cost savings if Ms. Carpenter's costs are typical: $500 for three unsightly barrels?
Let's try to put some numbers to my misgivings.
Let's assume that you, the rainwater stud, have 600 square feet of roof (half of a modest sized suburban home's roof area) and a 55 gallon rain barrel. Then it would take about 0.15" of rainfall to fill the barrel (using a conversion of 231 cu. in. per gallon). That means that after 0.15" of rainfall any additional rain is not captured!
Looking over the last six years of rainfall information in my own LA-area backyard (One of my not so private obsessions is rainfall statistics. I'm using my daily records of rainfall to make the tables below. You can do the same thing with a modicum of effort, an Excel spreadsheet, and the daily rainfall tallies for your area. Note to Steve Libby: Naturally I predicted the statistical utility of this data years ago when I started recording rainfall :-)
I'm also assuming I made no mistakes with the analysis, something that has not always proven to be the case, but the numbers seem to be what I expected and time is growing short so with an arrogant tip of my nose I'll take the "meets my expectation" observation as confirmation that they are indeed correct. Most of LA and a wide area of coastal southern California should be similar to what I present below. In fact, the inclusion of our driest year (06-07) and our wettest year (04-05) probably bounds the calculation for most of southern California: you should have results no worse and no better than predicted in those years.
Finally, with caveats and rambling prose out of the way, I can make the assessment of the impact that a rain barrel would have had on the rainwater stud's runoff, had he or she sited it in my backyard in any of the preceding six years:
There are two cases below. They use identical rainfall patterns (that of my back yard for the given years) and identical roof area (600 square feet). They differ in the size of the rain barrel. [Note that the number of down spouts doesn't matter. I assume ALL the rain from a 600 sq ft roof goes into the barrel or barrels. I'm writing this parenthetical note in response to a comment I received elsewhere suggesting that I add downspouts.] The upper table gives values for a 55 gallon rain barrel and the lower gives values for a 110 gallon rain barrel. In our recent wettest year, 2004-05, a 55 gallon rain barrel would only have been 11% efficient at capturing rainfall but would have been 65% efficient in our driest year (2006-07). For the case of the 110 gallon rain barrel the numbers are 19% and 99%, respectively. Average efficiencies are 0.47 for 110 gallon rain barrels and 0.29 for 55 gallon rain barrels.
 | |
| 55 gallon rain barrel, 600 sq ft of roof |
 |
| 110 gallon rain barrel, 600 sq. ft of roof |
I have to admit that the efficiencies are surprisingly high, particularly with larger capacity barrels. However, our assumptions tell us that our rainwater stud isn't always using the water when it's most needed in the garden, which is between storms. Instead, over consecutive storm days that exceed capacity the barrel has to be drained to get the kind of efficiencies that you see here: you actually would have to water with your barrel while it was raining in many cases. Consider also, that 600 sq ft of roof is only half of a small 50's era SFR roof. For larger homes the runoff will increase in proportion to the roof area driving efficiencies down for the two cases set forth above. I'll leave this post as it is now, with a high likelihood of a return visit to this topic later when I can stand to think about this again.
More locally-relevant information about rain barrels is contained in a fairly thorough document that does not address rain barrel efficiency at www.larainwaterharvesting.org.
2010-10-26
2010-10-25
Rain 0.28"; Season total 1.63"
0.08" on 23 Oct
0.20" on 25 Oct - nice overnight rain with beautiful blue skies on the morning of the 25!
A total of 0.28" in a couple days is the nice sort of rainfall that makes gardens grow.
We're in between rainfall totals from the previous 6 years at the same date: three were greater and three were less. If direct comparison to historical LA averages are to be trusted, we're well above both mean and median rainfall for the end of October, so we're running a little wet early in the season. Forecasters are predicting a dryer than normal winter, however, so it might be best to makehay while the sun shinesflowers while the rain falls.
0.20" on 25 Oct - nice overnight rain with beautiful blue skies on the morning of the 25!
A total of 0.28" in a couple days is the nice sort of rainfall that makes gardens grow.
We're in between rainfall totals from the previous 6 years at the same date: three were greater and three were less. If direct comparison to historical LA averages are to be trusted, we're well above both mean and median rainfall for the end of October, so we're running a little wet early in the season. Forecasters are predicting a dryer than normal winter, however, so it might be best to make
Corn maize
I visited the corn maze at Pierce College this weekend with Juli, Houston, and Chris. The maze makes Pierce College more money per acre than any other crop that they raise, according to them.
They give you a map of the maze before you start and you're supposed to use a distinctive hole punch at each of several waypoints to track your progress. The maps they give out are on postcards, but in case you need extra help there's always the signs.
I've done one maze elsewhere without the benefit of a map and it's very hard once you are inside,
Ariel photographs of previous years can be found online. The designs change from year to year and from the air it's clear that the mazes very accurately replicate their design. This year's maze, map pictured above, is complete with large letters spelling out "save the farm". Unfortunately, by this time in the season there were many unauthorized shortcuts through the maze so next time we'll try to go earlier in the season. That was really the only disappointment - being in a large maze is fun. We even got to see some huitlacoche:
Huitlacoche is supposed to be a great delicacy, but I thought it looked rather ghoulishly in keeping with the season.
Pierce College gets spooky after 7 pm. Here's the entrance to the corn field of horror or somesuch.
You have to pass beneath the gargoyle to encounter masked, chainsaw wielding psychos. Corny, or not?
- Posted at great expense from my iPhone
They give you a map of the maze before you start and you're supposed to use a distinctive hole punch at each of several waypoints to track your progress. The maps they give out are on postcards, but in case you need extra help there's always the signs.
I've done one maze elsewhere without the benefit of a map and it's very hard once you are inside,
Ariel photographs of previous years can be found online. The designs change from year to year and from the air it's clear that the mazes very accurately replicate their design. This year's maze, map pictured above, is complete with large letters spelling out "save the farm". Unfortunately, by this time in the season there were many unauthorized shortcuts through the maze so next time we'll try to go earlier in the season. That was really the only disappointment - being in a large maze is fun. We even got to see some huitlacoche:
Huitlacoche is supposed to be a great delicacy, but I thought it looked rather ghoulishly in keeping with the season.
Pierce College gets spooky after 7 pm. Here's the entrance to the corn field of horror or somesuch.
You have to pass beneath the gargoyle to encounter masked, chainsaw wielding psychos. Corny, or not?
- Posted at great expense from my iPhone
2010-10-24
Saffron crocus!!
Crocus sativus.
These took three years to produce. I've had the narrow leaves show in previous years, but never the blooms. I tasted a stigma straight from one flower and it was good!
I don't know what was different about this year as opposed to previous, perhaps the mild summer didn't dry them as much - they are said to produce better with supplemental water.
Wikipedia has some advice: "Timing is the key: generous spring rains and drier summers are optimal. Rain immediately preceding flowering boosts saffron yields; rainy or cold weather during flowering spurs disease and low yields. "
And
"Harvests are by necessity a speedy affair: after blossoming at dawn, flowers quickly wilt as the day passes. All plants bloom within a window of one or two weeks."
Looks like I missed the first harvest except for that one stigma.
- Posted at great expense from my iPhone
These took three years to produce. I've had the narrow leaves show in previous years, but never the blooms. I tasted a stigma straight from one flower and it was good!
I don't know what was different about this year as opposed to previous, perhaps the mild summer didn't dry them as much - they are said to produce better with supplemental water.
Wikipedia has some advice: "Timing is the key: generous spring rains and drier summers are optimal. Rain immediately preceding flowering boosts saffron yields; rainy or cold weather during flowering spurs disease and low yields. "
And
"Harvests are by necessity a speedy affair: after blossoming at dawn, flowers quickly wilt as the day passes. All plants bloom within a window of one or two weeks."
Looks like I missed the first harvest except for that one stigma.
- Posted at great expense from my iPhone
2010-10-23
Ooze on, L.A. River, ooze on
I picked up Keith & Rusty McNeil's California Songbook last summer while in Columbia.
The songs all relate in some way to California history and I like that they give a brief bit of historical context along with each song.
One of the selling points was this song at the back called L.A. River. Keith and Rusty write that the original author is anonymous, but that the song was taught to them in the 1960s by Clabe Hangan.
Lyrics to L.A. River:
There’s a river, a windin’ river, flowin’ through our town.
And it’s not so very mighty, but it sure does get around,
How I long to sit and cool my feet on its sterile banks of gray concrete,
Ooze on, L.A. River, ooze on.
Well it’s not so very mighty, and it’s not so deep and wide,
But its current has a longing to stay at low, low tide,
And I thank the Lord that it’s not blood red, but a peaceful, cool, green
algae instead, Ooze on, L.A. River, ooze on.
Now when the thunder sounds like fury and the rain begins to fall,
I dream that the mighty crashing is that river’s fearless roar,
But the sound I hear is not a dream, it’s a motorcycle goin` upstream,
Ooze on, L.A. River, ooze on.
Well it hasn’t any whitecaps, and it hasn’t any iish,
To see it splash and ripple, it would be my fondest wish,
But it floats its load of sad debris from the mighty sewer to the mighty sea,
Ooze on, L.A. River, ooze on.
Ooze on, L.A. River, ooze on.
- Posted at great expense from my iPhone
The songs all relate in some way to California history and I like that they give a brief bit of historical context along with each song.
One of the selling points was this song at the back called L.A. River. Keith and Rusty write that the original author is anonymous, but that the song was taught to them in the 1960s by Clabe Hangan.
Lyrics to L.A. River:
There’s a river, a windin’ river, flowin’ through our town.
And it’s not so very mighty, but it sure does get around,
How I long to sit and cool my feet on its sterile banks of gray concrete,
Ooze on, L.A. River, ooze on.
Well it’s not so very mighty, and it’s not so deep and wide,
But its current has a longing to stay at low, low tide,
And I thank the Lord that it’s not blood red, but a peaceful, cool, green
algae instead, Ooze on, L.A. River, ooze on.
Now when the thunder sounds like fury and the rain begins to fall,
I dream that the mighty crashing is that river’s fearless roar,
But the sound I hear is not a dream, it’s a motorcycle goin` upstream,
Ooze on, L.A. River, ooze on.
Well it hasn’t any whitecaps, and it hasn’t any iish,
To see it splash and ripple, it would be my fondest wish,
But it floats its load of sad debris from the mighty sewer to the mighty sea,
Ooze on, L.A. River, ooze on.
Ooze on, L.A. River, ooze on.
- Posted at great expense from my iPhone
2010-10-20
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