Major works at les Courmettes
Tuesday, April 23 marks the start of major works at les Courmettes. To combat summer drought, the estate is implementing four innovative projects that will ultimately enable better water management.
Forced to use tanker trucks in previous summers, the Courmettes estate decided last year to plan ahead and set up a working group on water management during the summer. At the same time, readings were taken over the summer period, and the results speak for themselves.
These data were measured last summer, when numerous water restrictions were in place. For example, water to the center and farms was systematically cut off between 11 p.m. and 7 a.m., and water-saving devices (aerators) and water recovery systems (water used to wash vegetables, some cooking water) were put in place for watering.
In addition, for the first time in 15 years, the estate resorted to having water delivered by truck.
It is therefore more urgent than ever for the sector to take action this year, and work is already underway on two of the four drought mitigation projects. So what do these four projects that will prevent a summer without water look like?
Project 1: Increasing water storage capacity
Problem: Water consumption at Les Courmettes during the summer period (June 15 to September 15) is double the capacity of these reserves during this period, i.e., 200 m3 of drinking water.
Objective: Increase storage capacity to supply the estate with the 400 m3 of water needed during this period.
Solution found: An additional 200m3 concrete tank will be built semi-underground and then concealed by a dry stone wall to blend in with the landscape.
Project progress: Excavators are digging a hole to place the tank, which must be at the same height as the current one to allow for similar filling.
Positive point: Of all the tank models proposed, the concrete version was chosen because it is more durable. The visual impact of this new tank is also considered to be less significant, as it does not disfigure the Courmettes landscape. In addition, the infrastructure will be covered in a second phase by photovoltaic panels.
2nd Project: Renovation of the spring catchment area
Problem: The spring collection system, which supplies 100% of the estate’s water, has been assessed by a hydrogeologist, who believes that the current system of open trenches mixes spring water with surface water (rain and runoff) in its collection. In addition, losses are suspected due to the bottom of the collectors (manholes) not being watertight.
Objective: Maintain a system that captures only spring water and prevent leaks from the collectors. Protect the area from wildlife to eliminate any risk of contamination.
Solution found: Create a uniform slope in the area where water is collected by filling in the trenches to allow natural drainage. This would allow only spring water to be collected. Install a regulatory protective fence around the area (PPI = Immediate Protection Perimeter).
Project progress: A team of volunteers, interns, and civic service workers, led by the estate’s building manager, cleared brush and rocks from the trenches on the land to facilitate the work of the excavators.
Positive point: The rocks recovered can be used to build a path border.
3rd Project: Maximizing the value of rainwater
Problem: Last summer, watering gardens was banned due to drought, meaning that the Courmettes estate was unable to keep certain species alive in its vegetable garden, which were intended for residents’ meals.
Objective: To store rainwater sustainably for use in the summer for watering, and even for showering or washing clothes, after it has been filtered.
Solution found: Improving the existing system by installing two additional 1,000-liter tanks to collect rainwater runoff from the estate’s 1,000 m² of roofing. A full day of rain would fill all of the tanks.
Project progress: Currently, three tanks with a total storage capacity of 4.5 m³ collect rainwater from a single 50 m² roof. In addition, a system for collecting water from vegetables and cold water from showers was already installed last summer.
Positive point: The pump that allows two tanks in the garden to communicate in case of overflow is powered by a solar panel, so the storage and recovery of rainwater does not consume any additional energy, making the project 100% renewable.
4th Project: Installation of urinals (without water) and dry toilets
Problem: Water used in the toilet drainage system accounts for 30m3 of consumption during the summer period.
Objective: To save 80m3 of water per year, while still providing access to certain conventional toilets. This would highlight the estate’s eco-responsible approach to the public (hikers, weddings, etc.).
Solution found: Installation of dry toilets based on the “KAZUBA” model (photo below) or waterless urinals.
Project progress: Still in the funding research stage, following the rejection of the application for the “Green Deal” project call for proposals by the 06 department in 2023.
Positive point: The toilets would provide compost, which would be collected annually at the end of the summer season. However, composting regulations require that this be done on a concrete surface.
These four projects are therefore part of the estate’s ecological and economic approach, and will enable it to meet its own needs and those of its residents next summer. Thanks to future and current investments in these projects, A Rocha France can see the Courmettes estate innovating year after year.
Victor Pommatau