Brake for Pantheon: Ministry Seeks Additional Environmental Assessment

The ambitious plan for the construction of the Pantheon data center Pantheon in Topusko to begin as early as 2027 is becoming increasingly difficult to achieve. The amendments to the Spatial Plan of Sisak-Moslavina County, without which the project cannot proceed towards permits, are still not completed, and the Ministry of Environmental Protection has now determined that as part of the strategic assessment, a Main Assessment of Acceptability for the ecological network must also be conducted.

The strategic study needs to be further supplemented precisely because the Topusko Campus was subsequently included in the amendments to the Spatial Plan in March, for which the Ministry has determined that the possibility of significant negative impacts on the ecological network cannot be excluded.

The process of adopting amendments to the Spatial Plan will thus be further delayed, although the fifth amendments and supplements to the Spatial Plan of Sisak-Moslavina County were initiated back in 2021. During 2022, a Strategic Study was prepared, and the proposed amendments to the Plan went through public discussion. However, the process was not completed afterward as both the Plan and the Study were further modified and refined.

New versions of the Plan and the Strategic Study were being developed during 2024 and 2025, but the amendments were still not adopted. In March 2026, their scope was again expanded, including the Topusko Campus, i.e., the interventions necessary for the planned data center and the corresponding energy infrastructure. Due to this expansion, a new preliminary assessment of acceptability for the ecological network was requested from the Ministry.

In September, the Ministry concluded that significant negative impacts on the ecological network can no longer be excluded.

We asked Domagoj Vranješ, the owner of Vita Project, a consulting company specializing in sustainable development and green transition, to estimate how long this process might take.

The Ministry has not yet received a request

– According to regulations, when an opinion is issued that significant impacts on the conservation objectives and integrity of the ecological network cannot be excluded for a strategy, plan, or program, a comprehensive strategic environmental impact assessment must be conducted, which includes a chapter on the main assessment of acceptability for the ecological network. Therefore, this is not a separate, parallel process, but a strategic assessment that encompasses that evaluation as well. In this case, this process follows the procedure for the development and adoption of the Spatial Plan of Sisak-Moslavina County – explains Vranješ.

According to him, such a process can take between six and 12 months, but even longer.

It is important to distinguish between amendments to the Spatial Plan and the assessment of the impact of the data center itself. The Spatial Plan establishes the planning assumptions for the realization of interventions at a specific location, while the impact of a specific project on the environment is assessed separately, based on its actual technical solution.

The Ministry of Environmental Protection and Green Transition confirmed to Lider that it has not yet received a request for the implementation of the procedure for the environmental impact assessment, the procedure for assessing the need for an environmental impact assessment, nor a request for an opinion on the need to conduct these procedures for data centers in Topusko and Nova Gradiška.

This means that environmental procedures for the projects themselves, according to the Ministry’s data, have not yet been formally initiated. In the case of Pantheon, this is quite understandable as the environmental procedure cannot be initiated while the intervention is not included in the spatial plan.

In the environmental impact assessment process for a specific intervention, possible direct and indirect impacts of the specific intervention on land, soil, water, air, climate, forests, population and human health, plant and animal life, biodiversity, landscape, material property, and cultural heritage are determined. If relevant for the project, its susceptibility to the risk of major accidents or disasters is also considered.

Key prerequisites

The assessment is conducted based on the Environmental Impact Study, which must also cover the use of natural resources and the impact of the intervention on water and water bodies. Cumulative impacts in relation to existing and already approved interventions are also taken into account. But what does such a procedure look like and how long can it take?

The process depends on the type, size, and characteristics of the project. For interventions subject to so-called screening, an assessment of the need for an environmental impact assessment, i.e., OPUO, is first conducted. In this process, the competent authority obtains opinions from other institutions and local government units, informs the public, and determines based on prescribed criteria whether a full environmental impact assessment is necessary for the specific intervention.

If it is determined that a full assessment is necessary, or if it is an intervention for which it is mandatory according to regulations, the investor initiates the environmental impact assessment process, i.e., PUO. The mandatory part of the request is then the Environmental Impact Study, which is prepared by an authorized person.

The Study is reviewed by a professional committee, which assesses its completeness, after which the documentation is sent for public discussion. Based on the Study, the committee’s opinions, and the results of the public discussion, the competent authority issues a decision on the acceptability of the intervention for the environment. If the project may also affect areas of the ecological network, the assessment of its acceptability for the ecological network is included in the process.

These procedures are conducted in the early stages of project development. A positive decision on the acceptability of the intervention for the environment is one of the prerequisites for the continuation of the project towards location and building permits.

However, this does not mean that the investor cannot undertake any activities before the completion of these procedures. According to Vranješ, they can purchase land, develop conceptual solutions and feasibility studies, sign letters of intent and pre-contracts, and request an opinion from the Ministry on the need to conduct a specific environmental procedure.

A lengthy process

But environmental obligations do not end with the data center itself. Power lines, transformer stations, solar power plants, and other accompanying infrastructure can represent separate interventions that, depending on their size and characteristics, are also subject to environmental procedures.

According to Vranješ, it is also possible for the Ministry to decide to consider the entire technical-technological system necessary for the operation of the data center through a unified procedure.

How long all this will take is difficult to determine precisely in advance. The preparation of the Environmental Impact Study for a large and complex project can take months as it requires data collection and measurements at the site. Some of the necessary foundations, such as biological or hydrogeological studies, may also depend on the season.

The public discussion in the full assessment process lasts at least 30 days, and the process can be further extended if the professional committee requests supplements or if additional questions arise during the public discussion.

According to Vranješ’s experience, the OPUO process lasts from two to six months from the moment a complete request is submitted, while a full environmental impact assessment for large projects can take a year or longer. This timeframe does not include the time needed for the preparation of the Study itself. Therefore, these two processes together last more than a year and a half.

His estimate is that if a request for a project of this size were submitted now, it would be unlikely that a final decision would be made before the second half of 2027, assuming that the Study has already been prepared.

Data centers in Croatia are not defined

An additional complexity regarding data centers arises from the fact that they are not separately listed in Croatian regulations as a type of intervention with its own threshold that automatically determines the obligation for an environmental assessment. The obligation is therefore determined based on the specific characteristics of the project and its location.

In the case of Topusko, the extraction of water for cooling is particularly relevant. The Ministry warns in the Decision that the Campus, in addition to an exceptionally large amount of electricity, will also require very significant amounts of water. It refers to American data indicating that the average water consumption efficiency of data centers in 2023 was 0.36 liters per kilowatt-hour of energy consumed by IT equipment, with a projected increase to 0.48 liters by 2028.

If these indicators were applied to the 5 TWh of annual electricity consumption that the Ministry cites for the four data centers in the Campus, it would result in approximately 1.8 to 2.4 million cubic meters of water annually, or an average of about 57 to 76 liters per second. This is not an estimate of the actual consumption of Pantheon as WUE in the denominator includes the consumption of the IT equipment itself, not necessarily the total consumption of the entire complex, but it shows why the Ministry has singled out the issue of water as one of the possible significant impacts. The chief designer of the Pantheon data center Mislav Crnogorac previously mentioned a consumption of about 100 liters of water per second, which would correspond to approximately 3.15 million cubic meters annually.

How much water the project will actually need will have to be determined, and this figure is important due to the environmental procedure: for the extraction of groundwater up to one million cubic meters annually, an OPUO is conducted before the county, for quantities between one and ten million cubic meters, the procedure is led by the Ministry, while for more than ten million cubic meters annually, a full environmental impact assessment is mandatory.

Additional environmental obligations for the Pantheon project may also arise from the energy infrastructure associated with the project. Regulations, among other things, provide for mandatory full assessments for solar power plants of 100 hectares or more, for power plants and energy plants with a capacity greater than 100 megawatts, and for power lines with a voltage of 220 kilovolts or more and a length of at least ten kilometers.

According to Vranješ’s estimate, the announced solar power plant with a capacity of 500 megawatts could occupy between approximately 500 and 750 hectares, which would be significantly above the prescribed threshold of 100 hectares for mandatory environmental impact assessment.

All this further illustrates how tight the announced start of construction of Pantheon in 2027 is, even assuming that the amendments to the Spatial Plan are completed soon.