Pilot interventions will be soon executed in the frame of Metro Adapt. These are small meteoric water management interventions; they are put in place by using Nature Based Solutions as an adaptation tool against increasingly extreme events. The interventions are now in the planning phase and will be carried out by CAP Holding in the coming months. They have evidential value. Technical visits to the construction sites are foreseen.
Solaro
The municipal sports facilities in Via Berlinguer are equipped with ample parking lot. The rain waters are currently being channeled into the town’s mixed sewage system.
The area of the Solaro sports facilities with the parking (lower left)
The intervention foresees the disconnection of the drainage network from the mixed drainage system and the delivery of rainwater in infiltration systems; in particular, a mixed SUDS system is envisaged. This will include:
- Two bio-restraint areas connected through a drainage trench (138 sqm) located in a marginal position of the parking lot. The drainage trench is designed for the direct drainage of the surface runoff water
- Two dispersion systems each equipped with 6 losing wells: one centrally located and the other one in a marginal position adjacent to the area of bi-maintenance
- Four draining flowerbeds (11 square meters each) in correspondence with the accesses to the sports field for the direct drainage of surface water.
Section of one of the 2 areas of bio-retention planned in Solaro
An example of bio-water conservation area for rainwater (Essen)
Location of areas of bio-restraint
Masate
Also in the case of Masate, the applied solutions are aimed at disconnecting the rain water from the mixed sewage system, in order not to overload both the net and the purifier that receives the waste water. The planned intervention involves a parking lot and an area of provincial road.
In blue: the road and the parking lot which will be disconnected
In green: the positioning of the detention basin
As the soil is not quite permeable, in Masate the infiltration of rainwater from the mixed sewage into the soil is not properly functioning. Therefore, the construction of a holding basin with a capacity of approximately 90 cubic meters (as per the planimetric section and the following section and subsequent example of a holding basin) is planned. The holding basin will allow the waters to be potted during heavy rains. In the hours following the meteorological events, the encased water will then be discharged in a small ditch (unfortunately buried due to urbanization), with a limited flow rate of 40 l / s per hectare of drained waterproof surface, as foreseen by the Protection Program and Use of the Lombardy Region Water.
Planimetry and section of the detention basin in Masate
An English example of “Detention basin” (www.susdrain.org)