Connecting to the water and sewer networks

Are you constructing a new building? Is your current building about to be connected to the water supply and/or stormwater network? Or is there going to be a pipeline renovation on your property? Please follow the instructions below (steps 1-10).

1. Obtain a map from the line location service of your building’s municipality

On the city’s line location map, you can see which utility lines run near your lot, i.e., which utilities can be connected to your property. If your property is included in HSY’s service area and/or stormwater sewerage area, the property is obliged to connect to HSY’s networks.

If you do not wish to join the water, wastewater or stormwater network, you can apply for an exemption from the obligation to connect. The line location map also allows you to verify in good time whether HSY’s water lines or sewers run on your lot.

2. Order a connection point statement

You will need a connection point statement as an attachment to your building permit application, and it will also be used as a basis for the property’s water and sewer plans ("KVV-suunnitelmat"). Read the instructions for ordering a connection point statement and order a connection point statement in the connection portal. Depending on the available capacity, the statement is typically delivered within 1 to 6 weeks of the order.

3. Apply for a building permit

Apply for a building permit from the building supervision department of your property’s municipality.

Remember that a permit is required not only for new buildings but also for pipeline renovations, extensions and connecting an existing building into utilities. In Espoo, Kauniainen and Vantaa, a building permit is not required for connecting an existing building to the stormwater network but, in Helsinki, a Z statement is required for this purpose. Please check with the building supervision department of your municipality whether an action requires a permit.

4. Order a connection and access contract and pay the connection fee

Order the connection and access contract in good time by filling in your details on the water contract order form. It takes about 2 weeks for the contract to be delivered. A connection point statement and an issued building permit are prerequisites for signing the contract. Connecting an existing building to the stormwater network also requires ordering a new contract. Read more about appendices to the water services connection and access agreement.

The contract must be signed by all owners of the property. We will send two copies of the contract, and the connecting party shall return both signed contracts to HSY. Then, HSY signs the contracts and sends the connecting party their copy of the contract as well as an invoice for the connection fee. Learn more about the fees for connecting to the water and sewer networks.

5. Submit the property’s water and sewer plans

Submit your property’s water and sewer plans to HSY via the work order and connection portal. We require the following for connections:

  • An equipment report ("KVV-laitteistoselvitys")
  • A layout plan ("KVV-asemapiirustus")
  • A floor plan ("KVV-pohjapiirustus") for the floor where the water meter space is located.

HSY is not responsible for the feasibility of the property’s water and sewer plans. HSY does not retrieve plans from the building supervision department’s Lupapiste permit service or accept paper plans. As the connecting party, you are responsible for submitting to HSY a version of the property’s water and sewer plans that matches the implementation.

If the plans specify connecting to HSY’s network using a pipe shared with another property, we will also need the contract on the shared pipes before the connection work is ordered. A signed contract on shared pipes can be submitted to HSY in connection with the property’s water and sewer plans via the connection portal.

6. Get a water and sewer supervisor for the property

The supervisor for water and sewer work ("KVV-suunnittelija") must be approved before the work on water and sewer systems is started. The supervisor is approved by the building supervision department of the relevant municipality.

7. Get a contractor for excavation and piping work

Get a contractor for your project to carry out the excavation and piping work on the property. HSY will perform the connection of main lines after the excavations.

8. Make a connection work order and book a connection time

You can order connection work via the work order and connection portal when the property has: 

  • a building permit (for projects that require one)
  • a water and sewer supervisor approved by the building control services
  • water and sewer plans submitted through HSY’s connection portal
  • a signed connection and access contract

When you have made the connection work order, you will be contacted to agree on the date for the connection work. Please note that you can also order the water meter at a later stage if it is not possible to install the meter during the connection work. 

Read more about the connection work fees:

Before the connection work, make sure that the excavation complies with the instructions. 

9. Order water meter installation

HSY installs the water meter either during the connection work or separately at an agreed time. If the water meter installation is not agreed on at the same time as the connection work, order the water meter installation via the connection and work order portal using the form “Ordering other work”. 

The water meter must be placed in an appropriate place so that it can be easily installed, read, serviced and replaced. It must be protected from freezing, heat and other harmful factors. 

The water meter is installed in a place stated in the water and sewer plan. The water pipe must be brought into the water meter space for the installation. The water meter is always installed in a horizontal position. If necessary, a pressure test is carried out for the lot water pipe when installing the water meter.