Implementation of Regenerative Hydrology
.jpg)
The implementation of regenerative hydrology solutions takes place over the long term. It is primarily about understanding how water functions on the plot, and then improving it. It is wise at each step to get training and support!
Steps to consider during implementation
Regenerative hydrology brings real benefits to the plot by improving water distribution (including excess water) but can quickly be counterproductive if poorly implemented.
First of all, it is important to conduct a thorough audit of the plot:
Weather history
The weather history on the plot is the first element to audit – especially to observe if there is a change in precipitation totals depending on the seasons. The IPCC does not fundamentally predict a decrease in precipitation over the year, but rather a decrease in summer and an increase in winter. In particular, intense episodes are expected so that water does not have time to infiltrate in winter, and dry periods lasting several weeks create significant water stress, for example when they follow spring frost periods.
Therefore, one must look at both monthly totals (and their evolution over about ten years) as well as recent intense episodes and observe the accumulation over several days.
Many websites allow access to these histories, for example on Meteoblue.
Soil profile
To understand well how the soil reacts in terms of infiltration, it is good to extract a profile… For this, one can dig a soil pit (or a profile with a telescopic tool) or at least perform a penetrometer test.
The goal is particularly to identify compactions and plow pans, which can block water in the subsoil and cause problematic hydromorphy.
Soil absorption capacity and water volumes
It is important to understand the volumes of water passing through the plot and that need to be infiltrated there.
To understand water volumes, one can refer to the chapter on the subject (see water paths).
Water absorption tests can also be done at various points on the plot (see absorption tests) – be careful to perform these tests with different soil conditions (dry or not). Perform the test preferably in winter to be close to intense rainfall conditions.
Plant needs
Finally, and not necessarily least important, it is essential to understand well the needs of the crops in place (productions and trees if applicable). Some plants, especially vineyards and fruit trees, require water stress to produce properly – it is wise to make system changes gradually to avoid going from one extreme to another!
Consider first the simplest approaches to implement
In general, it is important to consider gentle approaches first, then move towards structural modifications if necessary.
Cover crops, organic matter
Covers help slow water flows, protect the soil, promote infiltration through roots, etc. This is the first step regardless of the situation. Adding organic matter (OM) contributes to the soil’s capacity to retain water (a volume of 230m³ of water per hectare per additional % of OM is considered).
Hedges, riparian forests
Maintaining hedges along watercourses and ditches is an effective technique to prevent bank destruction and Erosion phenomena.
Fascines, fracturing
In case of runoff and ruts on the land, a first approach can be to install fascines, which slow water flows during heavy episodes and disperse water laterally.
A fracturing work (ideally along contour lines – see the article on keylines) is useful if the soil has an absorption capacity problem, especially in case of compaction.
Swales, ditches and other topography-modifying works
In a context of strong water stress (Mediterranean climate), it may be necessary to implement larger infrastructures such as swales or ditches, to store excess water during intense precipitation and infiltrate it over several days or even weeks. The sizing of these infrastructures requires specialist work and it is necessary to get advice in all cases!
Training
There are trainings on the subject of Regenerative Hydrology, particularly through Permalab but also via Alain Malard or Fabian Feraux.
Erosion TTool
The Erosion TTool project is a serious game that allows one to familiarize with different erosion control techniques: Erosion_TTool
