Senegal has a problem related to the availability of water quantity and quality. And yet, every year, 24 billion m³ of fresh water from the Senegal River escapes through the gates of the Diama dam and flows into the sea. It is in the analysis of these two antagonistic situations that we judge the problem of a paradox. The latter is the key to the motivation of this article in the field of water management. The unavailability of this precious liquid is aggravated by the overexploitation of the aquifers and the scarcity of rainfall. It should be noted that the boreholes, the KMS of Lake Guiers, the udder desalination plant are means provided by governments to stem the drinking water shortages that plague our populations. But all these efforts only temporarily alleviate the problems in question. We are signaling that the ideas of building projects such as the Cayor Canal, the Baol Canal and the water highways would be sustainable solutions to these problems. This is how we came up with the idea of a water transfer canal (the Canal du Centre) [1] . Its objective is to recover as much as possible from the 24 billion cubic meters of water lost to the sea downstream of the Senegal River and redirect it to the country’s arid areas to boost agriculture, on which 65% of the population depends [2] . It is an open-air canal lined with sand concrete and capable of carrying up to 70 m³/s of water by 2075, or 2.3 billion cubic metres per year. The volume recovered should be able to make available several tens of thousands of hectares of food and fodder crops. In addition, fossil valleys will need to be rebuilt, groundwater tables will need to be recharged, and millions of populations will be supplied with drinking water [3] .

The Following Formula (1) Makes It Possible to Estimate the Drinking Water Needs over the Project Horizon.

C = C₀ * (1 + a)p (1)

C: The average consumption of the project year here 2075;

C₀: The average consumption of the year the canal was put into service;

A: The increase in average consumption during the life of the project;

P: The number of years which separate the horizon and the date of commissioning of the project.

From pumping raw water into the Senegal River to redistributing drinking water to households and industries, the canal will experience various water losses. This article is limited to losses linked to evaporation, infiltration, and the purification of raw water [12] .

Apart from losses due to the purification of this water, all other losses will be calculated on the basis of raw water (water in the canal) [2] .

Therefore, the flow rates calculated in Table 3 must be multiplied by Kp = 1.2 to include the losses through purification.

Other needs include water for crops, for animals, for recharging aquifers and revitalizing fossil valleys. In order to assess these needs, we are going to take a flat-rate approach for animals and crops, granting each hectare of defined surface area a certain volume of raw water. Taking into account the types of crops planned, the volume retained is 50 m³/ha/day [13] [14] .

In reality, the total area planned for crops is colossal, 30,000 hectares of crops spread across the arid zones of the country. Its development will take place gradually over time ( Table 4 ) and its raw water requirements will follow the same trend ( Table 5 ).

Table 5 shows that demands for drinking and agricultural water will be minimal during the first years of the center canal (in 2025) and maximum over the project horizon (in 2075). And on the other hand, the demand for charging will evolve inversely. Therefore, it is appropriate to optimize the calculation flow of the canal section to minimize development costs. Using Figure 6 , let us closely analyze the changes in needs over time [15] [16] .

The agricultural and drinking curves represent changes in water demands over time.

The drinking + agricultural curve represents the sum of water needs for cultivation, households and industries.

The recharge curve estimates the flow of water that the canal will be able to transfer in addition to its design flow until 2075.

This graph ( Figure 6 ) shows that if the canal is sized for agricultural and drinking needs only, the recharge flow rates could be supported by the same section of canal until 2075. Table 6 gives the flow rates sizing [17] [18] .

Considering all these analyzes and calculations, an instantaneous flow rate of 68.503 m³/s is planned for the dimensioning of the center canal.

Water transfer projects have always been highlighted when proposing sustainable solutions regarding water supply in Senegal. The Cayor Canal should provide drinking water for the Thiès-Dakar conurbation and water for crops in Cape Verde and the Thiès region. The Baol canal with its four calculation variants should ensure the AEP of the Touba—Mbacké agglomeration, livestock and agriculture en route. The water highways are the result of the operation of three projects: the two previous ones and the fossil valley revitalization project. The latter is largely made up of penstocks [19] . The more sustainable and ambitious central canal is added to the list. It is because the relief allows it that it crosses the interior of the country from Bakel to Fatick, supplying all the regions it crosses. This article makes it possible to justify the feasibility of a water transfer channel capable of transporting several million cubic meters of water per day for decades [20] . These volumes will of course make it possible to supply the populations with drinking water and the land with water for crops, for the revitalization of dead valleys and for the recharge of aquifers. This project will mobilize more than 2.2 billion cubic meters of water each year from the Senegal River. All quantities of raw water will make available, among other things, 30,000 ha of arable land and 3.7 million cubic meters of drinking water every day. During periods of river flooding, many recharge areas may be flooded to recharge the water tables and many fossil valleys will be refilled. The route of this present canal showed a profile making gravity flow possible. However, its analysis was done according to the SRTM1 points file. This is raw data from topographic surveys. However, their accuracy is strongly dependent on the acquisition methods and the resulting artifacts [21] [22] . Therefore, we recommend a more elaborate survey campaign in order to acquire more precise point files. In addition, determining the minimum irradiation of the area where the installation of solar fields is planned could optimize the number of solar panels necessary for the construction of the photovoltaic power plant. This article defines technical parameters justifying the possibilities of constructing the canal and its impoundment. Therefore, other studies will be necessary for developments downstream of the center canal. These constructions include water treatment plants, hydro-agricultural developments, dams and sanitation for the discharge of wastewater, among others.