When Smaller Czech Construction Projects Trigger Mandatory EIA

10.4.2026 | ARROWS law firm

Are you building or planning to expand a commercial project? Do you think EIA does not apply to you because your project is not a major airport or motorway? You may be mistaken. In practice, environmental impact assessment standards are far stricter than most developers and investors realise. In this guide, you will learn when even an apparently smaller construction project is subject to mandatory EIA in the Czech Republic, what fines you may face, and how to avoid costly legal mistakes.

Quick summary
When and why a project is subject to environmental impact assessment
When a project changes – the risk of additional EIA
The EIA process in practice – what to expect
Key risks table and how ARROWS helps you
Duty to verify – how to proceed safely
Unified Environmental Opinion (JES)

Quick summary

Categories I and II: Projects are divided into two categories—some are always subject to EIA, while others go through a screening procedure.
Below-threshold projects: Even projects below the threshold must be notified if they reach at least 25% of the threshold value and are located in a specially protected area.
Project changes: Expanding production or the site area may trigger the EIA process if the change reaches the threshold values or 25% of capacity with a significant impact.
The “salami slicing” method is prohibited: Splitting projects into smaller parts to avoid EIA is unlawful and may result in substantial fines and the revocation of permits.
Practical risk: Carrying out a project without the required EIA opinion entails the risk of multi-million fines, a construction stop, and the invalidity of follow-on permits.

When and why a project is subject to environmental impact assessment

Environmental impact assessment (EIA) is not just administrative red tape for mega-projects. Act No. 100/2001 Coll., on Environmental Impact Assessment clearly sets out which projects must go through this process. The aim is to ensure that construction and activities do not have an unacceptable impact on the surrounding environment, water, soil, air, flora, and fauna.

In the Czech Republic, the regulation is strict and is based on Directive 2011/92/EU of the European Parliament and of the Council. The purpose of the process is to obtain an objective expert basis for issuing follow-on permits and to ensure that impacts on the environment and public health are taken into account.

ARROWS’ Prague-based attorneys deal daily with projects where investors have misunderstood what EIA requires. The result is often the risk of significant fines, a construction stop, and years of legal disputes. In practice, the rules appear simpler than they really are, because the Act contains a number of exceptions and conditional factors.

Classification of projects into categories

The problem starts with how projects are classified under Annex No. 1 to Act No. 100/2001 Coll. The Act classifies projects into two main categories:

Category I (Projects always subject to assessment): These are major developments such as oil refineries, nuclear power plants, motorways, airports with long runways, or large chemical plants. If your project falls under Category I, it must automatically undergo the full EIA process.
Category II (Projects requiring a screening procedure): This includes smaller but still significant projects—breweries, wind power plants, warehouse complexes, shopping centres, or car parks. Category II projects are not automatically subject to a full EIA, but must undergo a screening procedure.

Below-threshold projects

A third group consists of below-threshold projects that do not reach the threshold values set out in Category II. This includes, for example, smaller warehouses or buildings that remain below the specified thresholds by their parameters (e.g., a warehouse hall with a built-up area under 6,000 m²).

Attention—there is a risk here as well. A below-threshold project is subject to a screening procedure if:

It reaches at least 25% of the relevant threshold value; and
At the same time, it is located in a (national park, protected landscape area) or its buffer zone.

This is exactly where developers make mistakes, because the situation seems straightforward as the project is below the threshold. The competent authority may decide that even a below-threshold project requires a screening procedure if it meets the conditions and could have a significant impact on the environment.

When a project changes – the risk of additional EIA

One of the biggest risks comes later, when the investor decides to expand, modernise, or technologically modify the project. This is where the concept of a project change comes into play. If an EIA was issued for the original project and the client now wants to expand the development, they must be cautious.

The key rule under Section 4 of the Act is:

A change reaching the threshold value: If the capacity increase itself reaches the threshold value under Annex No. 1, the change is subject to a screening procedure.
A change reaching 25%: If the change has a lower capacity but reaches at least 25% of the capacity of the original project and the authority decides it may have a significant impact, it must undergo a screening procedure.

In practice, we encounter stories where an investor’s project came to a halt because, without the authorities’ knowledge, they expanded operations beyond the tolerated limit. The result may be a shutdown of operations, fines in the millions of Czech crowns, and complex legal proceedings for retrospective permitting. ARROWS’ Prague-based attorneys can help you navigate this change safely.

The “salami slicing” method – why it must not be done

The term “salami slicing” refers to a practice where a large project is divided into smaller parts and each part is assessed separately. This practice is prohibited by EU case law as well as decisions of the Czech Supreme Administrative Court.

Practical example: A developer plans a logistics park with a total built-up area of 15,000 m². To avoid the screening procedure, they split the project into three halls of 5,000 m² each and submit an application for each one separately at different times.

If the authorities prove functional and spatial links, they will label such conduct as circumvention of the law. This may lead to the revocation of permits and the need to carry out EIA retrospectively, which is economically and time-wise devastating for the investor.

Czech practice is strict on the “salami-slicing” approach, and the courts repeatedly confirm that functionally or structurally interconnected developments must not be assessed in isolation. What matters is the real functional interconnection and the cumulative impacts. The lawyers at ARROWS, a Prague-based law firm, can help ensure that your project is designed in compliance with the law.

Contact our experts

Mgr. Karel Huneš

associate

hunes@arws.cz

JUDr. Tereza Snopková, Ph.D.

associate

snopkova@arws.cz

The EIA process in practice – what to expect

If your project enters the EIA process, several stages await you.

Stage 1: Submission of the project notification

First, a project notification is filed with the competent authority (the regional authority or the Ministry of the Environment). The notification is prepared by an authorised person and must include information about the project, its location, capacity, and anticipated impacts.

Stage 2: Screening procedure

For Category II projects and changes, a screening procedure is carried out, where the authority generally has a time limit of 45 days to issue its conclusion. The authority examines whether the project may have a significant impact on the environment.

The outcome is the screening conclusion, which determines whether the project is not subject to further assessment or whether it proceeds to a full EIA. This also involves screening of impacts on the Natura 2000 network (Section 45i of the Nature and Landscape Protection Act).

Stage 3: EIA documentation and expert opinion

If an EIA is required, you must arrange for the EIA documentation to be prepared by an authorised person. This is followed by publication, comments from the public and affected authorities, after which the authority commissions an independent review expert opinion.

For developments near Natura 2000 sites, this may also include the so-called Natura assessment. This verifies impacts on Sites of Community Importance and Special Protection Areas.

Stage 4: Binding opinion

The process culminates in the issuance of a binding EIA opinion by the competent authority, which is an essential basis for subsequent permitting proceedings. The opinion is valid for 7 years and may be extended under certain conditions.

Timeframe

The screening procedure usually takes 2–3 months. If the project proceeds to a full EIA, the process from notification to the binding opinion typically takes 6 to 12 months, and longer for complex projects.

The attorneys at ARROWS, a Prague-based law firm, handle these processes on a regular basis and help prevent delays. Email us at office@arws.cz.

Table of key risks and how ARROWS helps you

Risks and sanctions	How ARROWS helps (office@arws.cz)
Fine for construction without a permit : Carrying out construction without the relevant permit (due to a missing EIA) may result in a fine of up to CZK 2 to 10 million under the Building Act (depending on the type of development).	ARROWS will verify whether your project requires an EIA and will provide legal oversight of the entire process.
Revocation of the permit : If a permit was issued without a mandatory EIA, it may be annulled by a court. Construction must be stopped and an order to remove the structure may be imposed.	ARROWS attorneys will represent you in dealings with the authorities and minimise procedural errors.
“Salami-slicing” approach : Detecting intentional splitting of a project leads to a requirement for a new assessment of the project as a whole and possible sanctions for circumventing the law.	We will help structure your project so that it complies with the law and does not face allegations of “salami-slicing”.
Financing blocked : For larger projects, banks require confirmation of EIA compliance (ESG standards). Without a valid opinion or screening conclusion, you may not obtain financing.	We will prepare a legal memorandum confirming that the procedure is correct for the bank or investor.

Specific examples – when you will enter the EIA process

To better understand where the line is, let’s look at the thresholds under Annex No. 1 to Act No. 100/2001 Coll. These thresholds are key for developers.

Retail and warehouse complexes

For retail complexes and shopping centres, as well as warehouse complexes, the threshold is 6,000 m² of built-up area. If you have a hall project with 5,000 m², you generally are not subject to mandatory screening, provided you are not in a protected area.

Car parks and garages

A separate category covers car parks or garages, where the threshold is set at 500 parking spaces. If you are building an office building with garages for 550 cars, you fall under the EIA process even if the building itself does not meet the threshold.

Residential development

Apartment buildings themselves do not have a direct area threshold in the legislation like warehouses do, but they may fall under so-called urban development projects. The threshold here is often 5 ha of the project area, but pay attention to locations in protected areas.

Wind power plants

For wind power plants, the threshold is very low: sources with output above 500 kWe or a tower height exceeding 35 metres are subject to screening. In practice, almost every modern industrial wind turbine meets this threshold.

Changes in industrial facilities

If you have a manufacturing plant and want to increase capacity, the rules on changes apply. Increasing capacity above the threshold or by more than 25% (if the threshold has already been exceeded or if the change has a significant impact) triggers the process.

The obligation to verify – how to proceed safely

If you are planning any more significant construction project, you should carry out a legal audit even before you start spending substantial money on a designer.

Step 1: Identify your project

Clarify the exact parameters, such as built-up area in m², number of parking spaces, production capacity, or building height.

Step 2: Compare with Annex No. 1 to the Act

Compare your project with the thresholds in Annex No. 1 to Act No. 100/2001 Coll. and determine whether you fall under Category I, Category II, or below the threshold.

Step 3: Consider a below-threshold project and the location

If you are below the threshold, verify whether you are located in a specially protected area (Protected Landscape Area, National Park) or a buffer zone. If so and you reach 25% of the threshold, you must submit a notification of a below-threshold project.

Step 4: Contact a lawyer

Before you submit an application to the authority, consult the procedure with experts. ARROWS, a Prague-based law firm, will provide a legal assessment and recommend a strategy.

Unified Environmental Opinion (JES)

With the new Building Act and the Act on the Unified Environmental Opinion (No. 148/2023 Coll.) taking effect, the processes are being integrated. The Unified Environmental Opinion (JES) consolidates a number of previously separate administrative acts in the field of environmental protection.

If your project is subject to an EIA, the output of the EIA process (the binding opinion) serves as a binding basis for issuing the JES, or is integrated into it. ARROWS attorneys can help you navigate the JES system and the new construction permitting procedure.

Table of detailed overview (Category II – screening procedure)

Type of project (Annex No. 1)	Threshold value (requires screening procedure)	Note
Commercial complexes and shopping centres	6,000 m² of built-up area	Item 10.6
Warehouse complexes	6,000 m² of built-up area	Item 10.6
Car parks or garages	500 parking spaces	Item 10.15
Wind power plants	Output > 0.5 MW or height > 35 m	Item 3.2
Leisure and sports facilities, hotels	Built-up area over 1 ha (in a protected area)	Item 10.8 (outside protected areas from 2 ha)
Wastewater treatment plants	Capacity from 10,000 to 100,000 PE	Item 1.9 (over 100,000 is Category I)
Extraction of mineral resources	Area from 5 to 25 ha	Item 2.5 (over 25 ha is Category I)
Changes to projects	Reaching the threshold or +25% of capacity/threshold	Under Section 4 of the Act

Conclusion

Environmental impact assessment plays a key role in the permitting process, because without a proper EIA opinion you will not obtain a building permit. You therefore risk significant penalties and a loss of value of your investment.

The rules are not trivial, and trying to circumvent the law does not pay off. The boundary between categories, the rules for changes to projects, and the specifics of protected areas require expert knowledge.

The attorneys at ARROWS handle EIA projects every day, and we know where the most common mistakes lie. The attorneys at ARROWS handle EIA projects every day. If you are planning a construction project, do not hesitate to contact our Prague-based law firm at office@arws.cz.

FAQ – Most common legal questions on EIA and development

1. I have a warehouse project with an area of 5,500 m². Do I need an EIA?
The threshold value for warehouse complexes is 6,000 m² of built-up area. If you have 5,500 m², you are below the threshold. However, if you are located in a specially protected area (e.g., a Protected Landscape Area), you must submit a notification of a below-threshold project, because you exceed 25% of the threshold.

2. I want to increase production capacity by 30%. Do I need to deal with a new EIA?
An increase in capacity by 30% exceeds the 25% threshold set by law for changes to projects. If the authority concludes that this change may have a significant impact on the environment, a screening procedure will be required.

3. Can I split the project into two phases so that each is below the threshold?
This is the so-called “salami method”, which is prohibited by law. Authorities assess projects in their aggregate (cumulatively), and if they demonstrate that it is a single project intentionally split, they will order an assessment for the project as a whole.

4. How long does the EIA process take?
In practice, the screening procedure takes approximately 2–3 months. A full EIA (if ordered) usually takes 6–12 months until the binding opinion is issued, depending on the complexity and the quality of the documentation.

5. What is JES?
JES (the Single Environmental Opinion) is an administrative act issued under Act No. 148/2023 Coll., which integrates multiple environmental approvals into one. If a project is subject to EIA, the EIA outcome serves as a basis for the JES.

6. What if the authority returns the EIA documentation for completion?
Returning the documentation for revision is common if it is not prepared to a high standard, and specific impact assessments (noise, water, nature) are often missing. This means delays of several months, which is why ARROWS works with top experts to help prevent this risk.

Disclaimer: The information contained in this article is for general informational purposes only and serves as a basic guide to the issue as of 2026. Although we strive for maximum accuracy, laws and their interpretation evolve over time. We are ARROWS Law Firm, a member of the Czech Bar Association (our supervisory authority), and for the maximum security of our clients, we are insured for professional liability with a limit of CZK 400,000,000. To verify the current wording of the regulations and their application to your specific situation, it is necessary to contact ARROWS Law Firm directly (office@arws.cz). We are not liable for any damages arising from the independent use of the information in this article without prior individual legal consultation.

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