Fight against drought with flood water

[jeandb]

I do not pretend to compare myself to Copernicus and want to place water at the center of the development of human activities.

But when I walk on a supermarket parking at noon in full sun I find that the temperature is surely higher than it would be if we had left the forest there was still a few centuries ago.

As I know, without being part of the thinking heads of the Giec or others that the planet is more and more covered with parking, highway, airports but also accelerates the flow of water by deforestation, drainage, embankment, I am say that the rainwater that does not enter the earth's crust of the continent raises the level of the sea. By adding the overexploitation of underground water reserves to Gaddafi and other agriculture in the African sun, etc., I also think that dry pebbles heat to a higher temperature than if the heat of the sun's rays could be used to develop the vegetation if they were iriguated.

Of course, all of this is not complete, clearly formulated, quantified, but when we have in front of us people who refuse the debate in a direction opposite to their convictions.

... especially if we bring a solution to the planet in danger.

[Woodcutter]

It seems to me that I know you, I must have had you by phone or by email 5 or 6 years ago ... About "Bief du Pilat" ...

All that to say that the management of rainwater is changing in France, it is necessary to keep abreast of the evolution of mentalities ...

[...] but when one has in front of oneself people who refuse the debate in a direction opposed to their convictions.

... especially if we bring a solution to the planet in danger.

Moreover, the volume of water flowing on surfaces impermeable by the action of man is tiny compared to the total volume of the hydrosphere.

Finally, you talk about irrigation for crops, but it's one of the worst ways to manage water in countries that lack it ...

[jeandb]

If attitudes have changed in France I can only be happy.

I do not know if I'm for anything but I remember that 25 years ago I had organized a meeting to explain my design to an entire assembly of 25 officials responsible for official organizations who were concerned about my water diversion experiments.
Faced with the position of the Director of Cemagref who took my defense by explaining that "I was going in the direction of history" while for several centuries we had been evacuating water to the river ....
I do not seek to earn money or notoriety but only to share knowledge.

As for the worst way to waste water, it's not crops as you think, but let the water go back to the sea.
Of course, this is not valid for inland seas, and water can not be removed by jeopardizing downstream activities.

[hic]

I do not pretend to compare myself to Copernicus and want to place water at the center of the development of human activities.

Hi jeandb

good idea *** store thunderstorms ***

an 1m3 tank is not enough,

I only see a pool of several m3


synergy
we do not water directly with tap water or rain,
we use it first for the pool (or others: cooling)

With dual use water is cheaper

the most efficient watering is underground watering,
is formed over a hard protective crust

[Grelinette]

I take again the interesting idea of ​​jeandb (and the title of this subject) to recover the excess of water (flood) to make reservations.

The recovery and storage of rainwater seems to me actually very interesting in several ways:

1 °) from what I could read, the storage of energy in the form of water reserve would have the best yield: of the order of 80%. (Besides, would someone have a comparative table of yields by type of energy storage?).

In short, recovering the rainwater from the plains to deliver them to dams in height (if of course the overall cost is not prohibitive) seems therefore an interesting solution from an energy point of view.
France is furrowed with pipelines for the transport of hydrocarbons: so we have the know-how, in addition, when it rains there is usually wind and this wind energy could also be used for the transport of water collected rainwater.

2 °) in recent years water shortages are becoming more important.
In addition to the energy storage of water, these reserves would serve to overcome the drought, especially since the opening of the valves in case of drought would activate the current-producing turbines.
We also hear that overall electricity consumption is higher in summer than in winter.

3 °) current urbanization is anarchic, galloping and unreflected has perverse effects that are observed every year: rainwater can no longer return to the groundwater, they follow paved roads, are channeled by buildings and end up concentrating at certain points with colossal energy. The damage caused each year is more important, for example, the floods of the Var in June 2010.
I lived in this area for several years and I still can not imagine that the small streams that were drying up in May could have turned into a tumultuous river that can still be seen on the internet videos online !

The anticipated management of these neglected flows would finally manage this wasted energy that always comes out.
For example, for any real estate project, individual and collective, a law requires the provision of rainwater management.

There is now a law that requires the provision of parking spaces for all constructions and connection to sewerage for wastewater; planning rainwater management seems to be the most basic of common sense.

As an example, I was recently discussing with an aeronautical engineer who was part of an advisory committee for the construction of an airport.
He had submitted the idea of ​​providing for the evacuation and recovery of colossal amounts of rainwater collected by the tarmac surfaces of the airport. Its recommendations have not been retained for questions of additional costs of the works, whereas the costs generated by future floods caused by rainwater collected and returned to the urban network will exceed a priori very largely the supplement of work upstream ...

4 °) in my department (Bouches du Rhône) we see more and more rainwater collection tanks (eg along highways, next to subdivisions, etc.).
For "normal" rains and thunderstorms, these reservoirs make it possible to avoid flooding, but there is now regularly exceptional rainfall with ever greater quantities of water, suddenly these collection reservoirs fill up and overflow: the flood problem is therefore only temporarily resolved!

[Christophe]

Nice raise of topic Hic!

Seen in a recent report: some farmers irrigate since 15 years with water from the sewage treatment plant (which would be rejected in a river otherwise).

It costs them € 5000 per fixed year, don't remember what city it is with! There is a 60km "private" distribution network.

Milan practices on a much larger scale (1 000 000 inhabitant) for years.

In France, we expect to be sure that the health risk is zero before extending the practice (I think that after 15 years we can begin to have certainties)

[cortejuan]

Hello,

I also saw the report and I wonder if the water was not used by farmers, it would go back to the rivers and would not be lost and possibly used by pumping for farmers so I do not understand really the added value of a parallel network. The problem for me is how to use water through agriculture. Water cannons are a huge waste of water because very little water finally feeds the plant. I do not have the numbers in mind anymore but we can say that maybe 70% go to the sky. The Arabs who were masters in the management of the water (gift transmitted to the Spaniards) used innumerable networks of channels and thus made the best use of water.

Oh yes, for corn it is not possible to use microchannels and if as suggested by Dumont in the 70 years we no longer plant this cereal greedy water in fertilizer and pesticide?

Everything is to rethink but frankly project cubic meters of water in the air to water a grain consumed by cattle, I want to sit down and cry.

cordially

[sen-no-sen]

Hello,

The problem for me is how to use water through agriculture. Water cannons are a huge waste of water because very little water finally feeds the plant. I do not have the numbers in mind anymore but we can say that maybe 70% go to the sky. The Arabs who were masters in the management of the water (gift transmitted to the Spaniards) used innumerable networks of channels and thus made the best use of water.
(...)
Everything is to rethink but frankly project cubic meters of water in the air to water a grain consumed by cattle, I want to sit down and cry.

While agreeing with you, however, the establishment of a drip system remains difficult to implement, especially with intensive monoculture, it would first challenge the agriculture itself ...

For the storage of water, it will be necessary to develop the construction of storm basins, which allow the recharge of groundwater, but also underground basin, the redevelopment of wetland area etc ...

[wampyr32]

Water cannons are a huge waste of water because very little water finally feeds the plant. I do not have the numbers in mind anymore but we can say that maybe 70% go to the sky.

We must stop talking about anything, at worst 10 15% are evaporated in the atmosphere during irrigation in very hot weather. (source Arvalis)

And this water is not lost, its evaporation decreases the ambient temperature and increases the local hygrometry, which has the effect of reducing evapotranspiration, decreasing the needs of plants.
It can also condense in the form of dew if the night temperatures are low enough and slow the temperature rise at the beginning of the day. But hey, it's fashionable to scream with the wolves rather than thinking 2 minutes ...

[cortejuan]

Hi,

Your sources seem different from mine but hey you're obviously a specialist in the thing maybe even a user of this solution.

Swing cubic meters of water in the sun is true that it is a good idea.

I remember that it is a way to lower the temperature ... interesting.

cordially