New 110kV underground cable connections will be built to replace the 110 kV overhead lines under construction to make way for the new Hiedanranta district and tramway. At the same time, all 110 kV overhead line sections between Lamminpää substation and Lielahti substation and Pölkkylänniemi terminal poles will be cabled.

110 kV underground cable connections to be built in the project:

- Lamminpää - Lielahti underground cable connection, includes the entire Lamminpää- Lielahti connection

- Lamminpää - Pölkkylänniemi underground cable section, includes part of the Lamminpää - Vesilinna connection

- Lielahti - Pölkkylänniemi underground cable section, includes part of the Lielahti - Ratina connection.

New 110kV underground cable connections (3x1x1600 Al) will be built to replace the 110 kV overhead lines (2 circuits, 1xDuck, freestanding poles, approx. 4 km) to be dismantled from the new Hiedanranta district and tramway under construction. At the same time, all 110 kV overhead line sections between Lamminpää substation and Lielahti substation and Pölkkylänniemi terminal poles will be cabled.

110 kV underground cable connections to be built in the project:

- Lamminpää - Lielahti underground cable connection (approx. 2.6 km), includes the entire Lamminpää- Lielahti connection

- Lamminpää - Pölkkylänniemi underground cable section (approx. 3.7 km), includes part of the Lamminpää - Vesilinna connection

- Lielahti - Pölkkylänniemi underground cable section (approx. 2.1 km), includes part of the Lielahti - Ratina connection.

Most of the cable routes have been or will be built in connection with the construction of other infrastructure (e.g. in connection with the construction of streets and tramways). Parts of the construction of the cable route may be included in the procurement. The dismantling of overhead lines is carried out in a different contract.