The southern part of Räätykänmäki and the western part of Silmäkeneva

Vasikkahaka and Silmäkeneva solar power plant site planning

The aim of the site planning is to enable the implementation of two industrial-class solar power plants. There are two project areas and they are located in the southern part of Räätykänmäki, in the field area east of the Vasikkahaa residential area, and in the western part of Silmäkeneva, east of the Kynttilätie industrial area. The areas are owned by HG Paloheimo Oy. In May 2025, the City Council decided to initiate the site planning of the areas based on the zoning application submitted by the company.

In connection with the station planning, the impacts of the projects are examined and comprehensive reports, plans and impact assessments are prepared for, among other things, the following entities: landscape, ancient monuments, nature, ecological connections, groundwater, stormwater, flood risk management, social impacts, climate and carbon impacts. The planning ensures sufficient protection zones for sensitive functions and values located in the environment.

On this page you will find information about the progress of the planning process, participation in the planning work, and the materials available for viewing.

Zoning application

HG Paloheimo Oy has submitted a zoning application for the preparation of a local plan and a local plan amendment for the placement of two industrial-scale solar power plants in areas it owns.

Planning area 1 is located southeast of the Vasikkahaa and Räätykänmäki residential areas in a field area and partly in an already zoned industrial and warehouse area at the end of Puhdistamontie. Planning area 2 is located in the Silmäkeneva area, east of the Kynttilätie industrial area, in a forested swamp area.

HG Paloheimo's application for zoning. (PDF file.)

Zoning decision

The Riihimäki City Board has decided to initiate the preparation of the town plan and town plan amendment in the areas covered by the application on 19 May 2025, Section 126.

City Council decision to launch zoning on May 19, 2025. (PDF file.)

A launch agreement has been drawn up to launch the planning process, which includes agreements on the launch of the planning process, the terms and conditions, and the planning objectives.

Later, after the draft plan is available for viewing, a land use agreement is drawn up between the contracting parties, which includes agreements on the rights and obligations related to the implementation of the plan: compensation for the benefits generated by the spatial planning, transfer of areas, and other implementation activities concerning the parties.
In connection with the station planning, comprehensive reports will be prepared to support the planning and impact assessment. Some of the reports are in progress and will be completed as the planning progresses.

Check out the completed reports:

Nature
Cultural environment and archaeology
- Archaeological inventory of the Herajoki solar power plant areas, Mikroliitti Oy, 2025. (PDF file.)
- Herajoki solar power plants, landscape survey, AJAK Oy, 2026. (PDF file.)
Architectural visualizations
- Herajoki solar power plants, illustrative photo compilation, AJAK Oy, 16.4.2026. (PDF file.)
Constructability
- Solar power plant foundation study, Silmäkeveneva, Regional Expertise, 2025. (PDF file.)
- Solar power plant foundation study, Vasikkahaka, Regional Expertise, 2025. (PDF file.)
The following reports are prepared during the proposal phase:
- Stormwater and flood risk assessment
- Groundwater survey
- Climate and carbon neutrality report
- Electricity transmission report
- Environmental assessments during construction

Initial stage of station planning

In the initial phase, the local planning process is announced and a participation and evaluation plan is published. In addition, surveys are prepared and the initial information needed for the planning process is compiled.

The initiation of the station planning process and the publication of the participation and evaluation plan have been announced in a newspaper advertisement in Aamuposti and an online advertisement on the city's website on April 18, 2026.

See the city's announcements. (kunta2.riihimaki.fi.)

Participation and evaluation plan

The participation and evaluation plan provides information on the progress of the planning work, objectives, impact assessment and opportunities to participate in the preparation. The participation and evaluation plan is visible throughout the planning work and is updated up to the planning proposal stage.

The participation and evaluation plan can be viewed on this website and on the planning notice board in the Veturi office at Eteläinen Asemakatu 4, 3rd floor.

Read the participation and evaluation plan. (PDF file.)

Kick-off presentation and discussion event

A presentation and discussion event on the planning and urban planning of the Vasikkahaka and Silmäkeneva solar power plants was organized on Thursday, May 7, 2026, starting at 5:30 p.m. at Riihimäki Eteläinen School. The event was open to everyone. The event was announced in a newspaper and online announcement and by letter to the neighborhoods in the planning area.

Read the memo and presentation materials prepared for the event. (PDF file.)

Leaving an opinion

You can leave your opinion about the participation and evaluation plan at the initial stage. The opinion can be in a free form. The opinion can be submitted to the Riihimäki City Registry Office at Eteläinen Asemakatu 2, PO Box 125, 11101 Riihimäki or by email to kirjaamo@riihimaki.fi.
Making the draft station visible

During the draft phase, a preliminary consultation of stakeholders will be organized by placing the draft plan material on display for three weeks. The display will be announced through a newspaper advertisement in the Aamuposti newspaper and an online advertisement on the city's website. Owners of properties bordering the plan area will also be informed about the display of the draft by letter.

The publication of the draft plan has been announced in a newspaper advertisement in the Morning Post and an online advertisement on the city's website on September 12, 2026.

See the city's announcements. (kunta2.riihimaki.fi.)

The draft town plans for the southern part of Räätykänmäki and the western part of Silmäkeneva will be on display from 14 September to 5 October 2026.

The station plan material (station plan map and description) will be available for three weeks on this website and at the Riihimäki Information Centre at Eteläinen Asemakatu 2.

Draft plan material on display:
The reports attached to the report can be found separately under Investigations.

Presentation and discussion event for the draft phase

A presentation and discussion event on the planning and urban planning of the Vasikkahaka and Silmäkeneva solar power plants was organized on Thursday, September 24, 2026, starting at 5:30 p.m. at Riihimäki Eteläinen School. The event was open to everyone. The event was announced in a newspaper and online advertisement and by letter to the neighborhoods in the planning area.

Read the memo and presentation materials prepared for the event. (PDF file.)

Leaving an opinion

You can leave your opinion on the content of the draft city plan during the draft stage. We recommend submitting your opinion in writing. You can submit your opinion to the Riihimäki City Registry Office at Eteläinen Asemakatu 2, PO Box 125, 11101 Riihimäki or by email to kirjaamo@riihimaki.fi.

See instructions for submitting an opinion during the draft plan stage. (PDF file.)
During the proposal phase, a plan proposal is prepared based on the draft plan. The planning process considers the statements and opinions presented during the draft phase and provides responses to them.

The City Council will consider the draft plan, including feedback, and decide whether to display it. The display of the draft plan will only be announced via an online announcement on the city's website. The draft plan will be displayed for 30 days.

Participants have the opportunity to leave comments on the proposed plan during the viewing period. During the proposal phase, statements are requested from the necessary authorities and communities.
After the proposal is on display, a revised local plan proposal will be prepared. The preparation will consider the feedback received during the proposal phase and provide responses to any objections and statements. The City Board will consider the revised proposal and decide to submit the plan to the City Council. The City Council will decide to approve the plan.

The approval of the plan will be announced on the city's website.

The parties and members of the municipality may appeal the city council's decision to approve the plan to the Hämeenlinna Administrative Court within a 30-day appeal period. The Administrative Court's decision can be further appealed to the Supreme Administrative Court.
The plan will become legally binding approximately 1,5-2 months after the city council's decision, unless there are any appeals against the plan.

The entry into force of the plan will be announced on the city's website.