|Upper Wawa Pumping Station||References_8792|
The Upper Wawa Pumping Station Project includes a pumping station for potable water of 518 MLD capacity (6 m3/s) that will serve the city of Manila as part of the Bulk Water Supply project.
The Employer of the project is Wawa JVCo and the EPC contractor is Prime BMD.
The project consists mainly of a pumping station hosted in a vertical shaft 65 m deep and 29 m diameter, a 2.1 km conveyor steel pipeline of 1.8 m diameter, an access road 1.5 km long, one access tunnel 1 km long in drill and blast, and three separate intakes consisting of steel lining suction tunnels equipped valves that will convey the water for the new WAWA reservoir to the pumping station inside the shaft. From there, the pumped water will be conveyed to the Calawis Water Treatment Plant.
Commissioning of the project is foreseen in December, 2024.
|Dietikon HPP - Upstream and downstream fish passages (MPP)||References_9847|
|Dietikon HPP - Upstream and downstream fish passages (EDPP)||References_9855|
|Greater Beirut Water Supply Project - General Planning||References_2000|
The project consists in the construction of a 24 km long headrace tunnel and 10 km of adduction pipes in order to exploit the Litani and Awali rivers for public drinking water supply. The water is drawn from a hydro power plant located in Joun, about 30 km from South Beirut, and conveyed to the Hadath and Hazmieh tanks, under design on the city uplands.
The water supply system is calculated to support future growing flow rates starting from 3 up to 9 m³/s and includes:
- 3 tunnels of about 24 km length and 2.8 m of diameter, excavated by 2
TBMs, and with a double ring of shotcrete and concrete coated with inserted
PVC waterproof membrane;
- 2 ventilation shafts, near the Damour syphon and a piezometric tank at the
North portal of Khalde;
- 1 syphon, which leads to a difference of 140 m in elevation and allows the
underground crossing of the Damour river. The connecting branches are
excavated into the rocks with conventional method and crossing in open air in
the fluvial deposits;
- 2 buried pipes, 10 km long and 1’400 mm of diameter each, both designed for
pressures up to 25 bar;
- 1 SCADA system for the plant control, which commands the numerous valves
of controlling and interception.
The watertight tunnel is designed taking into account low overburden and high pressure.
|Alto Piura Water Transfer||References_6453|
The Alto Piura Project is located in the north of Peru in the Piura Region, provinces of Huancabamba and Morropón, both on the east of Piura City. The aim of the project is to transfer water from the Huancabamba river situated on the east of the Peruvian Andes to the Pacific basin by means of a tunnel crossing through the Andes.
The Project includes various hydraulic infrastructure works and will have a significant impact on the economy of the region, as the water will serve to irrigate 50’000 ha of farmland providing 335 M cubic meters of water per year. In this way, the total area of irrigated land will increase by about 19’000 ha, which will contribute to expand the current agricultural exports of the region.
The main components of the Project are the Tronera Sur Dam, the Transfer Tunnel and the Access Roads.
The works at the Tronera Sur Dam comprise mainly a gated barrage with four radial gates (5.35 m high and 7.60 m wide) and a smaller radial gate (5.35 m high and 3.00 m wide). Additionally, there is a desander structure with 3 basins, each of them sub-divided into two smaller basins. The structure of the desander is approximately 51 m long and 44.8 m wide.
The stilling basin of the spillway is 38.5 m long and 41.4 m wide. The desander is equipped with a gated flushing system and an intake structure which is located in the channel of the Huancabamba river. The design flow is 26.4 m3/s which will be transferred by the 12.7 km long tunnel with a hydraulic section of 15.65 m2.
|Rehabilitation of Cassarate Penstock||References_6444|
AEM (Azienda Elettrica di Massagno SA) operates the hydropower plant Cassarate which exploits the flow of the rivers Cassarate and Franscinone in Canton Ticino (CH). The plant comprises a headrace tunnel at an elevation of 598 m. a.s.l. (maximum headpond water level) and a powerhouse at an elevation of 346 m. a.s.l. located in the Lugano suburbs. The hydropower plant has a gross head of 252 m and an installed capacity of 3.8 MW. The total length of the buried penstock, built in the year 1975, is about 1’520 m with a diameter of 1’000 mm.
The rehabilitation works consist in the renewal of the internal corrosion protection coating of the steel penstock and the decommissioning of the existing headpond, by means of directly connecting the headrace tunnel to the penstock.
The work phases of the renewal of the steel pipe are the following:
- Preparation of temporary openings in the penstock, cutting the pipe for a
length of 4 m in three points at equal distance, given that the diameter of the
existing manholes is not suitable for a good access into the pipe (450 mm);
- Removal of the existing internal protective coating byHDW (high pressure
water jetting) and sand blasting;
- Expansive cleaning and restoration of the existing corrosion pits inside the
pipe, by means of surface refining (grinding);
- Application of the new protective coating in 4 layers for a total thickness of
The existing Sonvico headpond will be decommissioned and bypassed by a PRFV pipe with a diameter of 1100 mm linking the headrace tunnel directly to the penstock. In fact, the headrace tunnel has a compensation volume of 16'000 m3, higher than that of the decommissioned basin, and the gross head of the HPP is slightly increased in the new configuration.
|Resses embankment - Villargondran (73)||References_6919|
|Gere HPP Waterway System||References_6445|
The Gere HPP was conceived in previous design phases as a traditional high-head scheme with a nearly horizontal, approx. 2 km long low-pressure headrace and an 800 m long buried penstock. The low-pressure headrace was designed as a tunnel with an exposed pressure line inside, as the tunnel was also intended to be used as access to the headworks during winter.
During the offer preparation for engineering services including tender, detail design, site supervision and commissioning, Lombardi as a member of the JV IGSL proposed a scheme modification with a 2.6 km long inclined tunnel from the powerhouse area up to the desander facilities and the Tirolean intake. The winter access function of the tunnel was maintained as in the original layout. The project was awarded to IGSL adopting this layout optimization.
Drill-and-blast underground excavation is carried out from the d/s portal only. The tunnel portal is located close to the powerhouse, easily accessible and just approx. 300 m from the designated dumping area. After excavation completion, the GRP-line is installed in the tunnel from u/s to d/s. It was possible to optimize and dramatically simplify site logistics compared to the original project layout: the two cableways for conveyance of the excavation material to the dumping area and for penstock installation are no more needed and the project environmental impact are further reduced.
Lombardi has been in charge of all conceptual and design project issues whereas our JV partner is responsible for project management and site supervision.