PIAN di MAGADINO (TI, CH)- TUNNELING

PURPOSES

This study, developed using FEFLOW software, analyzes the hydraulic impact of the future tunnel crossing the Magadino Plain, with particular focus on the effects on groundwater and the protected area of the Bolle di Magadino. A calibrated and validated three-dimensional numerical model was developed to simulate subsurface flow, taking into account stratigraphy, hydraulic properties, boundary conditions, and river dynamics (Ticino and Verzasca Rivers).

CLIENT

The Federal Roads Offfice (FEDRO), 2024-2025.

WHAT WE DID

Objectives:

Assess the tunnel’s barrier effect on groundwater flow.

Analyze local-scale impacts, particularly on the hydrological balance of the system and on the downstream Bolle di Magadino area.

Analyzed Scenarios:

Scenario 1: Open-cut excavation with sheet piling (“cut and cover”)

Scenario 2: Deep mechanized excavation using a TBM (Tunnel Boring Machine) 

Al MAKTOUM AIRPORT – Construction Dewatering Design, Dubai, UAE

PURPOSES

In 2019, a 3D groundwater flow model was developed to estimate dewatering volumes and evaluate a deep well system.
In 2024, the model was updated to reflect five years of operation and assess the impact of phased well deactivation.

CLIENT

Tristar Engineering LLC and AQUAGEO INTERNATIONAL CONSULTANCY LLC, 2019, 2024-25.

WHAT WE DID

Model Reuse & Upgrade: The 2019 groundwater flow model was reused, preserving its structure, layers, and boundary conditions.

Model Update: Integrated the current network of ~189 wells, including additions and removals based on actual implementation. Adjusted the model grid and remeshed for improved accuracy.

Calibration: Calibrated the model in steady-state using 2024 water level data due to the lack of long-term monitoring records. Applied real measured flow rates to test the model’s performance.

Performance Check: Compared simulated vs. observed water levels; discrepancies highlighted aquifer heterogeneity. Conducted sensitivity tests by adjusting pumping rates and hydraulic parameters.

Refinement: Fine-tuned hydraulic conductivities (Kx, Ky, Kz) and storage coefficient (Ss) to improve fit with field data. Achieved ~70–80% match with observed water levels, confirming a partially heterogeneous aquifer. 

Sustainable yield study based on pumping test data, Stabio (TI, CH)

PURPOSES

The Municipality of Stabio intends to extract water for thermal use (district heating) and re-inject it into the aquifer. Two test wells, P1 and P2, have been drilled, with flow rates of up to 1000 l/min for well P1 and 700 l/min for well P2. In well P1, the aquifer is under pressure, while in P2 it is not. The Municipality of Stabio aims to reach a pumping rate of between 3,000 and 4,000 l/min.

CLIENT

GEOLOG.CH, 2024.

WHAT WE DID

A 3D model was built, calibrated using the recorded data from the pumping tests, and then used to simulate scenarios with increased pumping rates by a factor of 4. A new well geometry, with wells of 800mm in diameter, was also tested. The simulations provided insights into the radius of influence and the corresponding drawdown for these scenarios.

Dewatering of Hassyan IWP construction site (UAE)

PURPOSES

Hassyan seawater reverse osmosis (SWRO) independent water project (IWP) is a major proposed water supply project to serve the Emirate of Dubai in the UAE.  The proposed pumping station for the project requires a deep excavation (about 14 m depth), which in turn will need dewatering of groundwater during excavation.  The pumping station position close to the coastline, which incorporates a Ramsar site, has prompted the need for a groundwater model, to understand impacts on nearby sensitive ecological receptors.

CLIENT

Aquageo International Consultancy, 2024.

WHAT WE DID

We enabled a realistic and dependable dewatering impact assessment of construction on groundwater levels at the sensitive habitat using a working 3D hydrogeological numerical model approach.

Dewatering works for the amplification of the sewage treatment plant “IDA-Giubiasco” (TI, CH)

PURPOSES

CLIENT

GEOLOG.CH, 2024.

WHAT WE DID

We enabled realistic and dependable assessment of dewatering needs (pumping rates volumes) to model and cross-compared various scenarios using a working 3D hydrogeological numerical model approach. A solution combining  a pumping system, such as dewatering pumps, at the bottom of the excavation pit and “sheet piles” around the excavation pit has been studied.

Dewatering works for the amplification of the sewage treatment plant “IDA-Vacallo” (TI, CH)

PURPOSES

CLIENT

GEOLOG.CH, 2024.

WHAT WE DID

We enabled realistic and dependable assessment of dewatering needs (pumping rates volumes) to model and cross-compared various scenarios using a working 3D hydrogeological numerical model approach. The following 4 solutions have been simulated:

CASE 1: Pumping system, such as dewatering pumps, at the bottom of the excavation pit.
CASE 2: Pumping system, such as dewatering pumps, at the bottom of the excavation pit, and “jetting columns” around the excavation pit.
CASE 3: Pumping system, such as dewatering pumps, at the bottom of the excavation pit, with secant piles along the road to block water along the river axis.
CASE 4: System of 23 wells with “deep wells” type pumps along the road to block water along the river axis.

Dewatering of “Stazione di pompaggio-ARM” (TI, CH)

PURPOSES

Estimation of dewatering rates of the construction site that requires dry conditions. 

CLIENT

GEOLOG.CH, 2023.

WHAT WE DID

We enabled realistic and dependable assessment of dewatering needs (pumping rates volumes) to model and cross-compared various scenarios using a working 3D hydrogeological numerical model approach.