4
$\begingroup$

I am not sure if I am asking it on a correct platform or not. A rainy river passes through my village. We suffer both in summer and in rainy seasons due to this. Could anyone explain how to recharge the ground water with river water. What would be the cost?

$\endgroup$
6
  • 4
    $\begingroup$ Divert the water into an artificial lake, which you empty in advance of rising waters, and from where you can take water in summer. Ground water however is practically only sourced from rain, and underground flows. Save it by keeping the ground covered by vegetation esp. in summer, and not pumping it up for agricultiural use. And yes, wrong platform here. $\endgroup$
    – Karl
    Jul 29, 2019 at 21:36
  • $\begingroup$ So I want to ask the OP for clarification, but they don't actually have an account here as the question was migrated...... $\endgroup$ Jul 30, 2019 at 19:41
  • 2
    $\begingroup$ @ThePowerHouse Hi. It looks like the chemistry mods migrated your question over here, where we talk about earth science. You say your village is in a climate with a rainy season (when the river floods) and a dry season (when the wells dry up). You can't really solve your problem by recharging the groundwater because a river is just where groundwater comes above the surface. But you can build a system to store groundwater during the rainy season to use in the dry season. Unfortunately, we don't have the expertise on this forum to recommend a solution or estimate a cost. $\endgroup$
    – Spencer
    Jul 30, 2019 at 22:31
  • $\begingroup$ There is, however, a Sustainable Living Stack Exchange and a more general Engineering Stack Exchange where there might be people experienced in designing water storage solutions in a cost-effective way. $\endgroup$
    – Spencer
    Jul 30, 2019 at 22:36
  • 1
    $\begingroup$ I have to disagree with Spencer, success of Managed Aquifer Recharge is far more about the hydrogeology that in the design of the water tub. In addition to the issues of sediment permeability, there are issues of insuring the water supply and minimising environmental effects of diverting water. And surely geological engineering shares earth science and engineering. $\endgroup$
    – haresfur
    Jul 31, 2019 at 22:58

3 Answers 3

7
$\begingroup$

The solution you are looking for is called "artificial recharge of aquifers" or "managed underground storage of recoverable water", among several other names.

Several different techniques have been developed for this in the past, and which one is applicable depends strongly on the specifics of your local situation. I'll describe the most frequently used techniques shortly, and link to two freely available e-books where you can look up all the details for planning your system:

  • Watershed management. This means the enhancement of natural recharge into the aquifer and involves a modification of large parts of the watershed of a local river. You can look into permaculture design techniques (swales, keyline ploughing and ponds) for suitable techniques. This is often the most suitable technique because it also helps in water management on local farms and prevents soil erosion and other damage by runoff water.

    Trees can play an important role in this technique. Up to a certain tree density of somewhere between 10% and 30% canopy cover, the benefits of trees for groundwater recharge outweigh the drawback that trees also consume more water. That is, when planting trees not too densely, they help to increase groundwater levels by keeping the pores in the soil open through which water can percolate down to the groundwater level. This is the result of some relatively new research, so the exact impacts and implications of this mechanism are not yet explored. The existing research work is available here and here, with an introductory article available as well.

  • Surface spreading. This category includes techniques such as recharge basins, modified stream beds, pits, shafts and others. The idea is to enhance percolation into the ground from surface area that catch stormwater. Maintenance often includes raking the bottom of recharge basins to prevent clogging from clay particles and other fines. Plus, this can only recharge into aquifers with no waterproof layers above them, and requires large land areas. But where this is possible, it is often the cheapest option.

  • Vadose zone wells. Also called recharge wells. Dry borehole wells or specifically drilled wells are used to recharge the aquifer. This can work with aquifers that have waterproof layers above them, but the main problem is clogging by fine particles over time, which cannot be effectively reversed. Overall, quite an expensive technique.

  • Aquifer storage and recovery (ASR) wells. Borehole wells that are designed both for recharge of the aquifer and recovery of water from the same well.

Relevant open access literature for further details and instructions:

  1. Prospects for Managed Underground Storage of Recoverable Water. Published by National Research Council. 2008. 351 pages.

  2. Source Book of Alternative Technologies for Freshwater Augmentation in Latin America and the Caribbean. Published by Unit of Sustainable Development and Environment, General Secretariat, Organization of American States. 1997. Here relevant: chapter "1.9 Artificial recharge of aquifers".

$\endgroup$
4
$\begingroup$

What you are asking about is called "Managed Aquifer Recharge" It has been successfully employed in some situations but depends greatly on the geology of the area. The aquifer needs to be relatively shallow with permeable sediments between it and the surface. If the sediments are not permeable (e.g. clay rich or solid rock) The water won't flow down to the aquifer in a reasonable time.

As one comment pointed out the water can be diverted into an artificial lake to drain slowly into the sediments. It also may be possible to form a lake by placing a dam on the river.

$\endgroup$
2
$\begingroup$
  1. Sand dam. A sand dam is a very low seasonal dam built on sand rivers....when it rains it usually just carries sand down. Bit the damage acts as an alluvial deposit. Slots in the dam allow water and silt to flow out. But the sand acts as a sponge holding water in dry days which can be well pumped or stored. enter image description here
  2. Ground recharge pit. Otherwise known as a percolation pit. Takes a standard bore well drilled initially for water... and modify with a filter and layers of rock, sand and filter fabric and activated carbon. When it rains or Floods water by gravity finds its way into the pit, drains and filters back into the well.[enter image description here]
  3. Zai: zais are unique in sense that they help soil. Available is a 1-2 foot wide by 1 meter deep hole. In farming preseason holes are filled with compost and manure and act as catchers for rainwater....then when it's time the area is planted. This system does not employ for ground water recharge but if accessory holes 3-9 meters deep are drilled they can allow 10-15% of the water to reintroduce into deep soil profile.
$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy