Wednesday, June 21, 2017

Rain Water Harvesting Infrastructure Design Concepts

Meandering Floodplains provide Real World Biomimetic Blueprints for Infrastructure Designs vrs Engineering Inspireded by Ambitious Human Business Venture Schemes
Image - ourwellnessway.com

The iconic classic movie, Chinatown, makes it abundantly clear that humans have always disrespected designs found in Nature, especially when their wouldview (based on blind faith) believes that such designs are an impedement to their economic business successes. This is certainly true with the history of Los Angeles where business development and growth hinged on aquisition of water, both it's abundance and controling it. LA’s legendary water superintendent William Mulholland was driven towards channeling this water from the Owens Valley to Los Angeles. But stealing water from far away north wasn't enough. Vast floodplains in Southern California had potential economic value for both agriculture and the creation of an industrial infrastructure. So the natural meandering physics of flowing water on floodplains had to be tamed and harnessed. Take for example this photograph above  with the meandering switchback pattern of the river. From a politics and businessman perspective, this impedes quick transportation of both people or goods. Logically (from a flawed human perspective) a straight channel direct line would seem to be the obvious choice. Same logic for getting rid of stormwater quickly from cities to prevent flooding, straight channeling seems the better choice. This is evident by all the straight floodcontrol channel infrastructure you can find throughout all of Southern California like the Los Angeles River below. Unfortunately, the path of least resistance hasn't always been the safest or most efficient route for moving human economic goals forward.

Photographed by Lane Barden

Industrial corridor of the Los Angeles River at the Seventh Street bridge in downtown Los Angeles, California

Image - Nature Conservancy - Stream Restoration
In my other post on Beavers and slow water movement, I had a cartoon at the top of the post of a beaver/builder constructung his dam. Other Beavers in the cartoon were on the river bank looking like eco-activists with protest signs demanding to have the dam torn down so that ALL of the river water could be used to irrigate the Pacific Ocean. But that really is no joke, because that is exactly how southern California has mandated it's floodcontrol infrastructure be designed for quick water movement supposedly to prevent flooding and endangering human beings and their businesses. But how well has that really been working for us ??? Often times channeled rivers, especially those in agricultural valleys channeled by earthen levees have been breached on many sides during high flood waters due to exceptional rainfall years. Like the photo here on the right where human modifications to the landscape strongly influences triggers to instability, accelerating the erosion potential and altering sediment transport and flow regimes of channels. Pay close attention to this picture of the Walla Walla River back in December of 1964 which defied human attempts at channelization and re-created it's former meanders, point bars, pools, and riffles. Can you click on the image and count how many right and left breaces there are ? That's just the nature of water and physical natural laws. By their very nature many people not only resent laws by humans, but also disrespect natural laws. These disastrous events are not so much the fault of nature as they are exposure of inept decision making by the elites among humans who believe they are above fault. After all, most of the scientific orthodoxy believes nature is flawed, imperfect and badly designed. (Okay, I won't go there, but you know it's true) In their worldview's paradigm the floodwaters should be managed as a waste product as something that should be gotten out of the system as quickly as possible. And so all floodcontrol infrastructure is really being considered as a greywater infrastructure with it's system of concrete pipes, culverts, channels, etc to facilitate water out of the urban environment as fast as possible to it's final destiny, the oceans. In reality, this is simply gross scientific ignorance where researchers have bought into their flawed worldview. Here's one man who battled the prevailing scientific orthodoxy in Germany & Austria while championing natural designs based on Nature most all of his life.
Institute of ecological Technology
In the early 1920s, Austrian Forester, Viktor Schauberger, also a self taught physicist and river engineer, was given the task of helping an Austrian Prince who became broke after World War I to improve his economy by finding a way to bring valuable virgin Timber down from remote mountain properties he owned which had no easy access. Timber in those days would had to have been hauled out with mule teams on less than ideal narrow roads through rugged country. Viktor Schauberger had a nature based scheme for building a unique log flume for transport which was very unconventional for the times. As with anything, logging flume design then consisted of straight walls and flat bottoms or at best flat bottoms with 'V' shaped design for the sides. But the flow dynamics were horrible. Schauberger's design was to be biomimic designs he had observed in Nature. He went with a half egg shaped design in which the flume would twist here and there like a snake in biomimicry of the meandering habit of a large river on a massive floodplain.
Very crudely designed log flume
Quebec, Canada
As the story was been told, Viktor Schauberger acquired the contract for building the flume caught the attention of the Estate Administrators and the Institute of Hydraulics at the University of Vienna. He was considered an anti-science Luddite by the science orthodoxy of his day. They hated the man. The day before it was due to be commissioned, Viktor decided to make a preliminary test of the flume's performance. An average-sized green beech log was ushered into the mouth of the flume and to his horror it stranded on the bottom after a few metres and would not budge. This wasn't supposed to happen according to he Natural designed flume calculations. Important dignataries, including his mocking critics were all going to be there at the grand celebration. After his workers were sent away to give himself some space to think, Viktor sat on a rock to ponder the situation. As he sat down he felt something scrabbling underneath his leather trousers and sprang up to his feet to find a snake. Grabbing it quickly, he flung it into the log holding basin, which supplied the flume with water and where the logs were to be assembled before being guided into the flume. As he watched it swim to the other side, he wondered how it was able to swim so fast. 

Illustration - giewasser.ch
Then he suddenly became aware of its peculiar serpentine 'S' shaped movement. It appeared like Nature had again came to his aid again. Calling his workers back, he ordered the holding basin to be drained and the log jammed up withing the flume removed. He then gave them instructions on how to attach thin wooden slats to the curved sides of the flume walls, which would act like the rifling in gun-barrels and cause the water to rotate anti-clockwise at left hand bends and clockwise at right hand bends. You can see the illustration blueprints here on the left. Working all through the night with the promise of double wages, the work was finished by early next morning ready for commissioning at the Grand Opening. The pond holding basin for the logs was refilled the next day in preparation for releasing the first logs. His critics were said to be dumbfounded by his unconventional flume design. Eventually the time came for the flume sluice-gates to be opened and the logs guided into the mouth of this half-egg-shaped channel. One particularly large beech log (which they did not want to test) managed to get itself included with the first few logs and, half way into the flume it suddenly jammed and the water began to back up behind it. While everyone there watched with anticipation, all at once with a loud gurgling sound it was sucked forwards and departed round the first bend. The other logs followed, passing easily down the flume, being kept away from the sides at the bends by those longitudinal vortices induced by the rifling slats which they installed the night before. Needless to say, it was a success, but maybe too much of a success. The Prince and his Princess got greedy and clear cut almost all the forest to increase their fortunes. Funny, nothing's changed one iota since the 1920s. Well, that's not true, it's actually worse.


Image - LifinLapland.com - Nellim Log Flume

While the early history of true biomimetics regarding hydrology is interesting, how does any of this benefit the average person today, especially in view of the further degradation of our planet's natural world that has been accelerated through the misuse and abuse of science ??? While there are some who truly believe in biomimicry of Nature, they are still greatly outnumbered by those who would trash Nature through the worldview argument of Nature being badly designed and only intelligent free-thinking humans can fix those flaws through scientific shortcuts. Okay, so change of pace here. There is an organization whose mission is to revitalize the contrete channelized L.A. River bed. who are known as the "Friends of the L.A. River". That's a tough assignment they've given themselves. Even during the lightest rainstorms, the greater L.A. infrastructure is human designed & engineered to rapidly facilitate storm water off the streets, parking areas, rooftops etc and efficiently send it rapidly on it's way down to the Pacific Ocean. This is an incredible waste of valuable freshwater resources. But believe it or not there are viable real world natural solutions to reduce runoff and redirect water into public and private landscapes and possibly percolate much of in into the subsoil layers of the ancient floodplains to be used later as well water. How much depends really on people being interested in change for the better. Below I'll provide a gallery of photos demonstrating how street rainwater harvesting techniques through biomimetics can change the present Hydraulic infrastructure and save disappearing fresh water resources from the outside of the region. Take a look, much of where this is already practiced is from areas with higher rainfall averages than Southern California like up north and back east.
Large City Street Landscaped Medians
Image - svrdesign.com

This is the central California city of Paso Robles, who are successfully positioning themselves at the leading edge of this municipal rainwater harvesting technology which biomimic's nature by the use of "baffles" which creates a switch back motion replicating the meandering pattern in the design & using periodic low dams called weirs (replicates beaver dams on small scale) which deliberately slows & backs up water raising the water level behind the weir in the planting bed that allows a good percentage of water to percolate deeper into deeper subsoil layers. Top photo illustrate what happens during storms and lower photo reveals an attractive look when dry. Utilizing native plants and having knowledge of how to encourage one gallon containerized seedlings to develop deeper root systems would truly help such plants make it without any further water assistence the rest of the year. There could be a minimal irrigation infrastructure of  deep irrigation designs, which would be utilized only in emergency summer situations to supplement and apply water three or four foot below the soil surface where most healthy California native plants want and prefer it. 
Image - svrdesign.com
Here in this picture above you can see the baffles which look to be recycled small guage railway track with a center concrete guide on top of a bed of cobblestones which allows the waters to slow down and remain clean prior to easing into the actual planting beds. Further cobblestones downstream are both functional for keeping soil intact, allowing further percolation and have a decorative purpose that biomimics a dry streambed which are common in California.
Image - hawkinspartners.com

Curb and Gutter Rainwater Harvesting for Landscapes in Business Areas and Residential Main Streets
Image - State Collage Pensylvania

Curb cut-out inlet to rain garden on west side of Allen Street near Pennsylvania State College. Just like a forest with meandering water courses and beaver dams, the goal here would not be to prevent water from reaching the oceans, but slow it way way down and make it work for the benefit of all sorts life along the way down.

Image - State Collage Pennsylvania

This rain garden is demonstrating weir flow during rain event. For those who may not understand what the word "weir" means. The term "weir" is a Dam-like barrier across the horizontal width of a landscape bed that alters the flow characteristics of the water and usually results in a change in the vertical height of the water level. There are many designs of weir, but commonly water flows freely over the top of the weir crest before cascading down to a lower level section of the landscape bed. Again, the purpose here is not to prevent water movement down stream, but rather to slow water movement down and percolation with drainage at the end for major storm runoff.

Image - State Collage Pennsylvania

Now here is the full entire length-wise view of rain garden on west side of this Allen Street. Everything here is functional and decorative all at the same time. The concrete weirs again back the water up in a small pond behind the artificially replicated beaver dam. With a series of weirs, this would also prevent erosion of planting bed materials just the way a series of beavers dams would accomplish on a real life floodplain in the wild.
Residential Neighbourhoods and other low Traffic Side Streets
Image - progress-project.eu


Image - greywateraction.org

Sidewalk bioswale treats street runoff in Portland, Oregon

In cities like San Francisco California and Portland Oregon, their storm drains are connected to their sewer treatment plants, and the potential for hazard for such infrastructure design is that heavy rains cause the sewer plant to overflow with raw and partially treated sewer water into the bay or river. Other cities connect their storm drains to underground creeks, and the polluted oily water runs straight into the bay or nearby river. By cutting curbs and digging sunken basins into the “right-of way” or “parking strip” area of the sidewalk, you can turn street rainwater from a problem into an actual resource. Diverted rainwaer that falls on streets can nourish plants, protect creeks, and contribute to cleaner cities as a result of the planter bed's healthy microbial community taking care of the pollutants & turning them into safer elements.


Image - svrdesign.com

Preventing and reducing water pollution can be as simple as building a rain harvesting curb cut for the garden. Once again, this runoff water from streets can come in contact with various substances to pollute it like chemicals from fertilizer, oil from cars and garbage, etc. Before this polluted water makes its way into storm drains and our riparian ecosystems, we would filter it through a natural rain collecting garden with a strong healthy microbial soil community to digest & process it. Rain gardens can also add to a home’s curb appeal and allow runoff water to filter naturally and deeply down through your yard’s soil. Keep in mind also that many of these structure as also designed with outlets and/or drains into runoff water pipes to allow for those extreme weather downpour events.
Commercial Parking Lot Medians and Dividers
Image - landskapsarkitektur.no

What amazes me with many of the beautifully designed landscape medians in many places like these parking lots is the fact that they exist in mainly higher rainfall areas like the northern & eastern parts of the USA, Canada and Europe, like this example above in Norway. What about Southern California where it is even more needed because they lack water ? Free water that is otherwise facilitated rapidly down the drain so that they basically are forcing themselves to use public utility provided clean drinking water to irrigate their commercial and home landscapes.

Bioswale parking lot created by Lynn Capouya Landscape Architecture

This is the kind of thing that really makes sense. Love the plant selection for the area and keep in mind that mulch is an important part of this bioretention system to really work effectively. Rocks and other smaller cobblestones are perfect for the slowing down of water movement and work perfectly as a mulch to keep the ground cool and retain moisture levels in soils. This is extremely important in parking lots where they create a massive heat islands.

Image - grownative.org
These Natives plants within the planter accompanied by a species abundant microbial community within the soil system are able to filter the runoff and protect streams. They can recycle the pollutants & turn them into nutrients that the plants can use. No stream or river pollution to kill aquatic critters in the water environment. Also runoff volume is greatly reduced (not stopped) which prevents the violent scouring of the natural local creek or riverbeds which allows the system to be stable, much like it was prior to human pavement. I would love to do something like this picture (minus the parking lot) for my mother's property with street curb back in El Cajon California. Unfortunately I'd have to be living back there permanently to maintain it. However having said that, look below at this Walmart parking lot in Santee California. 

Image - Google Earth

Walmart parking lot in Santee California

Last year in May/June 2016, my wife and I went back to my home town area of San Diego California and visited my mother who lives in the El Cajon/Santee area. Ignore the 2017 dates on the Google Earth picture, I just posted this to illustrate how illustrative it is of ir's improper design when they took this parking lot photograph. When we visited this exact parking lot (May 2016), it was 100+ F (40+ C) and I waited in the car while mum and wife went shopping. Half of those trees, irrigated by inefficient bubblers in a tiny planter median were dead or dying because they stopped watering them. Why did they cut back the water ? Because prices out there are outrageous, even when people have cut way back on watering like they were asked to in order to help buffer the shortages create by drought, the Water agency went and raised the water rates big time. Hence, the management decided the landscape was not worth the effort and expense. so the parking is nothing more than functional in purpose. Too bad and every customer who visits fights for that small shady spot for their car because of the effect of direct sun in 100+ degrees pushes inside temps 160+ degrees. 



The Landscape median mechanism designs for Successful Water Harvesting


Image - Empowerhouse
These are just some simplified animated illustrations to help provide an easy way to comprehend the design of the soil system withing the planter. Water enters into the cells through curb cuts and flows to an area planted with native plants (preferably native to the region that are attractive and ornamental looking) & a microbial community system that are known to remediate heavy metals and toxins that vehicles usually leach on to the street, not to mention the totally unnecessary Agro-Chemical products used by commercial & home owner landscapers. The water is filtered through the topsoil where most of the roots are and then into a type of mixed gravel bed which will hold and store the bulk of the floodwater only then to seep slowly back into the subsoil layers and possibly as far as the moist ground water supply which helps to alleviate runoff to local waterways.  Usually this rain water runoff would enter directly into the storm system, where it could lead to an increase in combined Sewer Overflows that contribute significantly to the pollution in our rivers and streams.

(Image courtesy of GeoSyntec Consultants)

Stormwater runoff flows into this type of bioretention area like the other one above, percolates through the soil (which acts as that bio- filter) and eventually drains into the groundwater; some of the water is also absorbed by the plants. Bioretention areas are usually designed to allow ponded water and with an overflow outlet to prevent flooding during larger storm events which are becoming more common. Where soils have low permeability or where faster drainage is desired, designers may incorporate a perforated underdrain that routes to a storm drain system. If you have a soil profile like my mother's place which is built on top of an ancient alluvial floodplain, then such drains may not be necessary. But if you have a clay or adobe type soil profile, then I'd recommend the drainage. 
Nice Video Resources
This video surprisingly comes from the State of California. I say it's a surprise because you cannot see very much in the way of people practicing this water harvesting technique out there, with the exception of the Palm Springs & Coachella Valley areas.
http://www.waterboards.ca.gov/stormfilm


This video below is excellent as it provides a how to for boring a hole through the curb and sidewalk to allow a inlet for stormwater to enter into the landscape strip.



This final link comes from Arizona. Actually it is a separate post I created because Arizona is much further along on this biomimicry and their climate almost mandates such a practice be done over there. And besides I thought it would have cluttered this post up with more info than it already has. 😏
Tucson Arizona: Regenerating Parks & Parkways through Biomimicry of Floodplains


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