The Illinois Water Use Act of 1983, specifically Section 5 of the Act (765 ILCS 75/5), outlines the requirements for a landowner to be able to divert or use water from a surface water source for agricultural purposes without needing a permit from the Illinois Department of Natural Resources (IDNR), provided certain conditions are met. The key provision is that the landowner must have been engaged in the “agricultural use” of the water for at least the preceding 10 years. This establishes a grandfathered right based on historical usage for agricultural purposes. The Act’s intent is to protect existing agricultural water users while allowing for new uses under regulated conditions. The 10-year continuous agricultural use establishes a right to continue that use. This does not, however, grant an absolute right to increase the diversion beyond what was historically used for agricultural purposes without potentially triggering other regulatory considerations or the need for a permit if the increased use is substantial and impacts other users or the source itself. The Act focuses on protecting established agricultural practices from being disrupted by new users seeking permits. The 10-year threshold is a critical element in establishing this protected status for agricultural water use in Illinois.

Illinois operates under a system of common law riparian rights, modified by statutory provisions and the public trust doctrine. Under common law riparian rights, ownership of land adjacent to a watercourse grants rights to use the water. However, these rights are correlative, meaning they must be exercised reasonably and without unreasonable interference with the rights of other riparian owners. The Illinois Water Use Act of 1983 (415 ILCS 5/8.2 et seq.) establishes a framework for water use, particularly concerning significant withdrawals. While Illinois does not have a prior appropriation system like many western states, the Act does require registration of certain large-volume water withdrawals and provides for potential regulation if significant adverse impacts on water resources are identified. The public trust doctrine, as interpreted in Illinois, holds that the state holds its navigable waters in trust for the benefit of the public, impacting the ability of private entities to claim exclusive rights to water use. Therefore, a landowner in Illinois seeking to divert a substantial quantity of water from a navigable stream for industrial purposes would need to consider not only their riparian status but also potential state regulatory oversight and the overarching public trust obligations. The specific quantity that triggers registration or significant concern is defined by the Illinois Department of Natural Resources (IDNR), often based on daily or annual withdrawal volumes. Without explicit statutory authorization for such a diversion that overrides these principles, the landowner’s rights are limited by the reasonable use doctrine and the state’s regulatory and trust responsibilities.

In Illinois, the concept of riparian rights, which is based on common law, generally grants landowners adjacent to a watercourse the right to reasonable use of that water. However, Illinois has also adopted a permit system for certain water uses, particularly for significant withdrawals, which overlays and modifies the common law riparian doctrine. The Illinois Department of Natural Resources (IDNR) oversees the regulation of water resources through the Illinois Water Use Act of 1983. This Act requires permits for substantial water withdrawals, generally defined as exceeding 100,000 gallons per day or 3,000,000 gallons per month, from any source within the state. The purpose of this permitting system is to manage water resources efficiently, prevent waste, and ensure equitable distribution among users, especially during times of scarcity. Landowners who withdraw water within these thresholds are typically not required to obtain a permit, but their use must still be reasonable and not infringe upon the rights of other riparian landowners. The Act also establishes a framework for water conservation and planning. Therefore, a landowner withdrawing 90,000 gallons per day from a stream bordering their property in Illinois would not require a permit under the Water Use Act of 1983, assuming their use is reasonable.

The Illinois Water Use Act of 1983, specifically 525 ILCS 45/1 et seq., establishes a framework for managing water resources in Illinois, particularly concerning high-capacity water wells. A key provision of this Act addresses the registration of existing high-capacity wells. A well is generally considered “high-capacity” if its pumping rate exceeds 100 gallons per minute. The Act mandates that owners of such wells must register them with the Illinois Department of Natural Resources (IDNR). This registration process is crucial for monitoring water usage, assessing the impact of withdrawals on groundwater resources, and ensuring compliance with water management objectives. Failure to register a high-capacity well as required by the Act can result in penalties. The Act does not require registration for wells with pumping rates below this threshold, nor does it impose a general registration requirement on all groundwater users. The focus is on those withdrawals that have a significant potential to impact the resource.

Illinois operates under a system that balances riparian rights with a permit system for water use. While the state recognizes the rights of landowners adjacent to water bodies to use that water, significant appropriations, particularly for commercial or industrial purposes, require a permit from the Illinois Department of Natural Resources (IDNR). The Illinois Water Use Act of 1985 (45 ILCS 85/) establishes a framework for managing water resources, aiming to prevent waste and ensure equitable distribution. This act mandates that any person intending to withdraw more than 100,000 gallons of water per day from any source in Illinois must obtain a permit. The permit process involves demonstrating a beneficial use of the water and adherence to regulations designed to protect the resource from depletion and degradation. Factors considered in granting permits include the impact on existing users, the environment, and the availability of the water source. The concept of prior appropriation, common in Western states, is not the primary basis for water rights in Illinois; instead, the focus is on reasonable use and the permit system for large-scale withdrawals. Therefore, a landowner seeking to withdraw a substantial amount of water for agricultural irrigation, exceeding the daily threshold, would need to navigate this permit process.

Illinois follows a system of water rights that, for surface water, is primarily based on the doctrine of riparian rights, modified by statutory provisions. Under this system, landowners whose property abuts a body of water have rights to use that water. However, these rights are correlative, meaning they must be exercised reasonably so as not to unreasonably interfere with the rights of other riparian owners. The Illinois Department of Natural Resources (IDNR) plays a crucial role in regulating water use, particularly through the permitting process for certain activities. While riparian rights are generally considered to attach to the land, the specific exercise of these rights can be subject to regulation to prevent waste or unreasonable use, especially during times of shortage. The concept of “beneficial use” is central, although it is often applied in conjunction with the reasonableness standard. For groundwater, Illinois operates under a rule of “absolute ownership” or “rule of capture” for percolating waters, meaning a landowner can pump as much groundwater as they wish from beneath their land, even if it depletes neighboring wells, provided the pumping is not malicious or for a use outside the state. However, this rule has been subject to some judicial limitations and legislative attention, though its application remains largely intact for groundwater. The Illinois Water Use Act of 1983 requires permits for certain high-capacity water withdrawals from both surface and groundwater sources, aimed at monitoring and managing significant water use to ensure availability and prevent adverse impacts. This permit system is a key mechanism for state oversight, even within the framework of riparian rights for surface water and the rule of capture for groundwater. The question tests the understanding of the primary legal doctrines governing water rights in Illinois for both surface and groundwater and the role of state regulation.

The Illinois Water Use Act of 1983, specifically Section 8, addresses the process for registering a “large capacity water withdrawal” which is defined as a facility that withdraws more than 100,000 gallons per day from a single source or multiple sources within a 1,000-foot radius. The Act mandates that any person intending to construct or operate such a facility must register it with the Illinois Department of Natural Resources (IDNR) within 90 days of commencing operation. This registration is crucial for the state to monitor and manage water resources effectively, especially in areas experiencing or at risk of water scarcity. Failure to register can lead to penalties. The Act also establishes a framework for resolving conflicts related to water use and promotes the conservation and efficient management of water resources throughout Illinois. Understanding the threshold for registration and the reporting timeline is fundamental for compliance with Illinois water law.

Illinois operates under a riparian rights system, modified by the doctrine of reasonable use. This means that landowners adjacent to a water body have rights to use that water. However, these rights are not absolute and are limited by the correlative rights of other riparian owners. The concept of “reasonable use” is central, meaning a riparian owner can use the water for purposes connected to their land, but not in a way that unreasonably harms other riparian owners’ ability to use the water. This includes uses for agriculture, domestic purposes, and even some industrial uses, provided they are reasonable and do not cause substantial depletion or pollution that negatively impacts downstream users. The Illinois Department of Natural Resources (IDNR) plays a role in managing water resources, particularly concerning large-scale appropriations and permits for certain water uses, but the fundamental rights are rooted in common law riparianism. In situations of scarcity, the focus shifts to equitable allocation among riparian users based on the reasonableness of their respective uses and needs. The Illinois Water Use Act of 1985 further clarifies some aspects of water use, particularly for significant withdrawals, requiring permits and promoting efficient management. The core principle is that no single riparian owner can claim exclusive or excessive use to the detriment of others.

In Illinois, the framework for water rights is primarily based on the doctrine of riparian rights, though it is modified by statutory provisions and administrative regulations. Riparian rights attach to land that abuts a natural body of water. Under this system, landowners whose property borders a stream or lake have a right to make reasonable use of the water. The Illinois Water Use Act of 1983, specifically 415 ILCS 60/1 et seq., is a critical piece of legislation that governs water use in the state. This Act establishes a permit system for certain high-capacity water withdrawals, particularly for agricultural irrigation and industrial uses, to ensure efficient and sustainable management of water resources and to prevent undue depletion of water sources. The Act requires permits for withdrawals exceeding a specified daily volume, which is currently set at 100,000 gallons per day. The purpose of this permitting process is to monitor water usage, assess potential impacts on other users and the environment, and to facilitate coordinated water resource management. Failure to obtain a required permit can result in penalties. Therefore, any entity proposing to withdraw water above the statutory threshold must navigate this permit application process with the Illinois Department of Natural Resources (IDNR). The Act also emphasizes the importance of water conservation and the prevention of waste.

The Illinois Water Use Act of 1983, specifically Section 8, addresses the process for a new user to establish a right to water. When a new user proposes to divert water from a surface water source in Illinois for a beneficial use that would exceed 100,000 gallons per day, they must provide notice to the Illinois Department of Natural Resources (IDNR). This notice is a critical step in the process. The IDNR then has a statutory period to review the proposed use and may impose conditions to protect existing lawful uses and the environment. Failure to provide this notice can result in penalties and the inability to legally establish the water right. This requirement is a cornerstone of the state’s approach to managing its water resources by ensuring that significant new withdrawals are documented and assessed. The Act aims to balance the needs of new users with the protection of established water rights and the ecological integrity of water sources within Illinois.

In Illinois, the doctrine of riparian rights, as modified by statutory provisions, governs the allocation of water resources. While riparian owners have rights to reasonable use of water adjacent to their property, these rights are not absolute and are subject to the correlative rights of other riparian owners. The Illinois Department of Natural Resources (IDNR) plays a significant role in water management, particularly concerning large-scale appropriations and projects that may impact water availability. The Illinois Water Use Act of 1983 (415 ILCS 5/8) establishes a framework for water use, requiring permits for certain withdrawals exceeding specific thresholds, thereby ensuring a more orderly and sustainable allocation of water resources. This act aims to balance the needs of various users, including agriculture, industry, and municipal supply, while also considering environmental flows and the health of aquatic ecosystems. The concept of “reasonable use” is central, meaning a riparian owner cannot use the water in a way that unreasonably harms other riparian owners. This often involves a balancing of the needs and the impact of the use. For instance, a large-scale industrial withdrawal that significantly diminishes the flow of a stream to the detriment of downstream agricultural users would likely be deemed an unreasonable use. Conversely, a small domestic use would generally be considered reasonable. The IDNR’s permitting process evaluates proposed water uses against these principles, considering factors such as the source of water, the quantity proposed for withdrawal, the purpose of the use, and the potential impact on other users and the environment. The Act also addresses the potential for water shortages and provides mechanisms for managing such situations.

The Illinois Water Use Act of 1983 governs the appropriation and use of water resources within the state. Under this Act, any person proposing to construct a new facility or expand an existing one that will require a significant amount of water, defined as an average daily withdrawal of 100,000 gallons or more, must register their intended water use with the Illinois Department of Natural Resources (IDNR). This registration requirement is a crucial aspect of water management in Illinois, aiming to ensure that water resources are used sustainably and equitably. The Act establishes a system for monitoring water use and identifying potential conflicts or shortages. While Illinois operates under a modified riparian rights system, the Water Use Act of 1983 introduces a registration and permitting framework for large-scale water users, which is distinct from the common law principles that govern smaller, non-commercial uses. The IDNR is responsible for administering this Act, including maintaining records of registered water uses and evaluating the impact of these uses on the state’s water resources. The Act does not create a system of prior appropriation in the same vein as many western states, but rather a registration system that informs the state’s water management efforts and can lead to the development of water use plans or restrictions if necessary to protect the public interest and the environment. The threshold for registration is a key detail, as it distinguishes between uses that are subject to this specific regulatory oversight and those that are not.

The Illinois Water Use Act of 1983 governs the appropriation and use of surface water and groundwater in Illinois. It establishes a permit system for significant water users. A “significant water user” is defined as an entity that withdraws or proposes to withdraw 100,000 gallons or more of water per day from a single source or multiple sources for a common purpose. This threshold is crucial for determining who falls under the regulatory purview of the Act and must obtain a water use permit from the Illinois Department of Natural Resources (IDNR). The Act aims to manage water resources sustainably, prevent waste, and ensure equitable distribution among users, especially in times of scarcity. It also addresses issues related to the correlative rights of landowners to groundwater. The permit process involves an application detailing the proposed use, source, volume, and impact on other users and the environment. The IDNR reviews these applications to ensure compliance with the Act’s objectives and may impose conditions on permits. The 100,000 gallons per day threshold is a key trigger for this permitting requirement, distinguishing between minor uses and those that necessitate formal regulation to protect the state’s water resources.

Illinois follows a riparian rights system modified by statutory provisions. Under common law riparian rights, landowners adjacent to a water body have a right to reasonable use of that water. This right is correlative, meaning it is shared with other riparian landowners, and no single owner can unreasonably interfere with the use by others. The Illinois Water Use Act of 1983 (50 ILCS 215/) establishes a permit system for certain large-scale water uses, particularly for agricultural irrigation, and also addresses water conservation and management. Specifically, the Act requires permits for any person proposing to withdraw more than 100,000 gallons of water per day from any single source or combination of sources for agricultural irrigation. This permit requirement is a key statutory overlay on the common law riparian doctrine. The Illinois Department of Natural Resources (IDNR) is the agency responsible for administering this permit program. The Act aims to balance the needs of agriculture with other water uses and to promote efficient water management, especially during periods of water shortage. Without a permit for agricultural irrigation exceeding the statutory threshold, the withdrawal is considered unlawful.

Illinois follows a system of riparian rights, modified by the doctrine of reasonable use, which governs water allocation for surface waters. Under this system, landowners whose property abuts a watercourse have the right to make reasonable use of the water. Reasonable use is defined as a use that does not unreasonably interfere with the use of the same water by other riparian owners. This doctrine balances the needs of individual landowners with the collective right to water resources. Factors considered in determining reasonableness include the character of the use, its extent, its suitability to the locality, and the impact on other users. For instance, agricultural irrigation, while a common use, must be conducted in a manner that does not deplete the stream to the detriment of downstream riparian owners. Similarly, industrial uses must also adhere to the principle of not causing unreasonable harm. The Illinois Environmental Protection Agency (IEPA) plays a role in regulating water quality and discharges, which indirectly impacts water availability and use by ensuring that water remains suitable for its intended purposes. The state’s Water Use Act of 1983 also addresses water management, particularly concerning large-scale water withdrawals and conservation efforts, but the fundamental allocation of surface water among riparian owners is primarily governed by the common law doctrine of reasonable use.

Illinois operates under a system of common law riparian rights, modified by statutory provisions that allow for the appropriation of water for beneficial uses. When a conflict arises between users concerning surface water, the doctrine of reasonable use is applied. This doctrine posits that each riparian owner has the right to make reasonable use of the water flowing past their land, provided that such use does not unreasonably interfere with the use of other riparian owners. The determination of what constitutes “reasonable use” is a factual inquiry that considers various factors, including the character of the use, its extent, purpose, and suitability to the location and surroundings, as well as the harm caused to other users. Unlike prior appropriation states that rely on a strict “first in time, first in right” principle for surface water, Illinois’ approach emphasizes balancing the needs of all riparian proprietors. The Illinois Water Use Act of 1983, while primarily focused on groundwater, also informs the broader context of water resource management within the state by promoting conservation and efficient use. The core principle for surface water disputes remains the common law doctrine of reasonable use, which seeks to prevent waste and ensure that the rights of all riparian landowners are respected in a manner that promotes the overall beneficial use of the water resource.

The Illinois Water Use Act of 1983, codified at 525 ILCS 45/1 et seq., establishes a framework for water use in the state. A critical aspect of this act pertains to the reporting requirements for significant water withdrawals. Specifically, the Act mandates that any person who owns or operates a facility that withdraws more than a specified daily volume of water must register that withdrawal with the Illinois Department of Natural Resources (IDNR). The threshold for mandatory registration is a daily average withdrawal of 100,000 gallons or more. This registration requirement is designed to enable the state to monitor and manage water resources effectively, particularly in areas experiencing water stress or potential conflicts over water allocation. The Act prioritizes reasonable use and aims to prevent waste and unreasonable impairment of existing water uses. Failure to comply with registration requirements can lead to penalties. The context of a large-scale agricultural operation in Illinois, such as the one described, would necessitate adherence to these reporting mandates if its irrigation systems collectively draw water exceeding the 100,000-gallon daily average threshold from any source, including groundwater or surface water. The Act’s provisions are foundational for understanding water rights and regulatory obligations for substantial water users in Illinois.

In Illinois, the doctrine of riparian rights, as modified by the Public Water Supply Act (415 ILCS 45/) and related case law, governs the allocation and use of surface water. While riparian owners generally have rights to reasonable use of water adjacent to their property, these rights are not absolute and are subject to the public interest and the state’s regulatory authority. The Illinois Department of Natural Resources (IDNR) plays a crucial role in managing water resources, particularly concerning large-scale appropriations or uses that could impact other users or the environment. The Water Use Act of 1983 (45 ILCS 45/) establishes a framework for permits for certain water uses, aiming to ensure efficient and equitable distribution. A key principle is that no single riparian owner can unreasonably interfere with the rights of other riparian owners. Furthermore, the state retains inherent authority to regulate water use for the common good, which can override private rights when necessary for public health, safety, or welfare, especially during periods of scarcity or for the protection of aquatic ecosystems. The concept of “reasonable use” is central, meaning a riparian owner can use the water adjacent to their land for purposes connected with that land, but not to the detriment of downstream users or the environment. The Illinois Environmental Protection Agency also has a role in regulating water quality, which indirectly affects water availability and use.

The Illinois Water Use Act of 1983, specifically 525 ILCS 45/1 et seq., establishes a framework for water use registration and reporting. The Act mandates that any person who owns or operates a facility that withdraws groundwater or surface water in an amount exceeding 100,000 gallons per day on average for any 30-day period must register their water withdrawal with the Illinois Department of Natural Resources (IDNR). This registration requirement is a cornerstone of the state’s efforts to monitor and manage its water resources effectively, particularly in areas experiencing significant demand or potential scarcity. The Act aims to provide a comprehensive inventory of major water users, which is crucial for informed water resource planning, allocation, and conflict resolution. Failure to comply with the registration requirements can result in penalties. The threshold of 100,000 gallons per day for a 30-day average is a key detail in determining when a withdrawal becomes reportable under the Act. This threshold is applied to the average daily withdrawal over a continuous 30-day period, not necessarily a calendar month. Therefore, a facility withdrawing an average of 99,000 gallons per day for 29 days and then 101,000 gallons per day for 30 days would not meet the registration threshold if the 30-day average is below 100,000 gallons. However, if the average over any consecutive 30-day period reaches or exceeds 100,000 gallons per day, the registration obligation is triggered. The Act does not require registration for withdrawals that consistently remain below this threshold, even if they are substantial in absolute terms. The focus is on identifying and monitoring the largest users to ensure sustainable water management practices across Illinois.

Illinois operates under a Riparian Rights system, modified by common law principles and statutory provisions. The Illinois Water Use Act of 1983 (5 ILCS 145/) is a key piece of legislation that governs water use. This act establishes that all waters within the state are public waters for the use of the people of Illinois, subject to appropriation and use in accordance with the provisions of the Act. It also addresses the concept of reasonable use, which is central to riparian doctrine. Reasonable use means that a riparian owner can use the water on their land for any purpose, as long as that use does not unreasonably interfere with the use of other riparian owners. This includes agricultural, industrial, and domestic uses. The Act further specifies that if a person proposes to withdraw more than 100,000 gallons of water per day from any single source, they must notify the Illinois Department of Natural Resources (IDNR). The IDNR then reviews the proposed withdrawal to assess its impact on other users and the environment. The concept of prior appropriation, common in western states, is not the primary system in Illinois. Instead, the focus is on riparian ownership and the reasonable use of water resources by those who own land adjacent to the water body. The Illinois EPA also plays a role in water quality regulations, but the primary framework for water *use* and withdrawal, particularly for large quantities, falls under the purview of the IDNR and the principles of riparian rights and reasonable use.

In Illinois, the doctrine of riparian rights, as modified by statutory provisions, governs water use. While riparian owners have rights to use water adjacent to their land, these rights are not absolute and are subject to reasonable use limitations and the public interest. The Illinois Department of Natural Resources (IDNR) plays a crucial role in regulating water use, particularly for significant withdrawals. The Water Use Act of 1983 (45 ILCS 85/) establishes a framework for managing water resources. Section 7 of this Act (45 ILCS 85/7) specifically addresses the requirement for permits for certain water withdrawals. A permit is generally required for any person or entity proposing to withdraw more than 100,000 gallons of water per day from any single source or combination of sources. This threshold is a key regulatory point. Therefore, an entity proposing to withdraw 120,000 gallons per day from the Kankakee River would indeed require a permit from the IDNR, as this quantity exceeds the statutory daily limit. The underlying principle is to ensure sustainable water management and prevent undue strain on water resources, especially during periods of scarcity. The IDNR evaluates permit applications based on factors such as the impact on other water users, the environment, and the availability of the water source.

Illinois follows a system of riparian rights, modified by the doctrine of reasonable use. This means that landowners whose property borders a body of water have the right to use that water. However, this use must be reasonable and not interfere with the rights of other riparian owners. The Illinois Environmental Protection Agency (IEPA) plays a crucial role in regulating water use through permits, particularly for significant withdrawals. The Illinois Water Use Act of 1985 (415 ILCS 5/1 et seq.) establishes a framework for water use reporting and management, requiring permits for certain withdrawals that exceed specific thresholds, generally defined by volume and duration. The Act aims to prevent waste, promote conservation, and ensure equitable distribution of water resources, especially during times of scarcity. When evaluating a new appropriation, the IEPA considers factors such as the applicant’s proposed use, the impact on existing users and the environment, and the availability of water in the source. The concept of “beneficial use” is also paramount, meaning the water must be used for a purpose that is recognized as serving the public good and is not wasteful. In Illinois, the Department of Natural Resources (IDNR) also has a role in managing water resources, particularly concerning surface water appropriations and flood control. The principle of “prior appropriation” is not the dominant doctrine in Illinois; instead, it is the riparian doctrine with its emphasis on reasonable use and the regulatory oversight by state agencies that governs water rights.

The Illinois Water Use Act of 1983, specifically Section 8, addresses the registration of high-capacity water withdrawal facilities. A facility is considered high-capacity if its aggregate withdrawal rate exceeds 100,000 gallons per day. The Act requires that any person constructing or operating such a facility must register it with the Illinois Department of Natural Resources (IDNR). This registration process is crucial for the state to monitor and manage water resources effectively, especially in areas experiencing water stress. Failure to register a high-capacity well can result in penalties. The Act does not mandate a specific permit for all water withdrawals, but rather a registration for those exceeding the defined threshold. The concept of riparian rights, while present in some water law systems, is largely superseded in Illinois by the statutory framework for water use management, particularly for significant withdrawals. The IDNR is the primary agency responsible for administering the Water Use Act and maintaining the registry of high-capacity wells.

In Illinois, the doctrine of riparian rights, as modified by the state’s water use and conservation statutes, governs the allocation and use of surface water. While riparian owners have rights to reasonable use of water adjacent to their property, these rights are not absolute and are subject to the public interest and the prevention of waste. The Illinois Department of Natural Resources (IDNR) plays a crucial role in regulating water withdrawals through its permitting process, particularly for significant quantities of water. The Illinois Water Use Act of 1983 (5 ILCS 100/1 et seq.) establishes a framework for managing water resources, emphasizing conservation and equitable distribution. This act requires permits for substantial water withdrawals, defined by specific volume thresholds, and aims to balance the needs of various users, including agriculture, industry, and municipal supply, while protecting the environment. The concept of “reasonable use” is central, meaning a riparian owner cannot divert water in a way that substantially harms other riparian owners or the public interest. This includes preventing waste, degradation of water quality, or depletion of the source. Therefore, any substantial diversion of water, even by a riparian owner, typically requires a permit from the IDNR to ensure compliance with the state’s water management objectives and to avoid infringing on the rights of others or the public trust doctrine. The threshold for requiring a permit is generally 100,000 gallons per day, as per the Act, although specific regulations may detail further requirements or exemptions. The IDNR’s oversight is designed to manage finite water resources sustainably.

In Illinois, the doctrine of riparian rights, as modified by statute, governs water use. Riparian rights attach to land that abuts a natural body of water. Under Illinois law, riparian owners have a right to make reasonable use of the water, provided such use does not unreasonably interfere with the use of other riparian owners. The Illinois Department of Natural Resources (IDNR) plays a crucial role in managing water resources, particularly concerning large-scale appropriations or projects that might impact water availability. While Illinois does not have a prior appropriation system like many western states, it does have provisions for permits for certain water uses, especially for significant withdrawals or for purposes like industrial cooling or irrigation that could affect downstream users. The Illinois Water Use Act of 1983 (45 ILCS 85/) is a key piece of legislation. It establishes a framework for managing water use, including requirements for permits for high-capacity wells and for certain agricultural uses. The Act emphasizes conservation and the prevention of waste. When considering a new, substantial agricultural irrigation project in Illinois, a primary legal consideration for the developer would be compliance with the Illinois Water Use Act of 1983. This Act requires a permit for any well that pumps more than 100 gallons per minute (GPM) or more than 100,000 gallons per day. Such permits are reviewed by the IDNR to assess potential impacts on groundwater resources and other users. The concept of “reasonable use” is central to riparian rights, meaning a use that is not wasteful and does not materially diminish the quantity or quality of water available to other riparian owners. The IDNR’s permitting process is designed to ensure that proposed uses align with these principles and do not create undue hardship or conflict among water users.

In Illinois, the primary framework for water rights is riparianism, which is modified by the doctrine of reasonable use. This means that landowners adjacent to a watercourse have the right to use the water, but their use must be reasonable and not unduly interfere with the rights of other riparian owners. The Illinois Water Use Act of 1983, specifically Section 415 ILCS 20/1 et seq., establishes a permit system for significant water withdrawals exceeding a certain daily threshold, which is currently 100,000 gallons per day. This Act aims to manage water resources sustainably and prevent depletion. If a proposed withdrawal exceeds this threshold, a permit from the Illinois Department of Natural Resources (IDNR) is required. The permit application process involves demonstrating that the withdrawal is for a beneficial use and will not cause undue harm to other users or the environment. The concept of “beneficial use” is broad and can include agricultural, industrial, municipal, and recreational purposes. However, the reasonableness of the use is always a factor, even with a permit. For instance, an agricultural user might have a permit, but if their irrigation practices lead to excessive water loss through evaporation or runoff, or significantly lower stream flows to the detriment of downstream users, their use could be deemed unreasonable, potentially leading to permit modification or revocation. The IDNR also considers the impact on groundwater levels and surface water flows when evaluating permit applications. The Illinois State Water Survey often provides data and analysis to inform these decisions, assessing the availability of water resources in specific basins.

Illinois follows a riparian rights system, modified by the doctrine of reasonable use. This means that landowners whose property abuts a watercourse have the right to use the water. However, this use must be reasonable and not interfere with the rights of other riparian owners. The Illinois Environmental Protection Agency (IEPA) plays a crucial role in regulating water quality and issuing permits for water appropriations and discharges, primarily under the Illinois Environmental Protection Act and the Illinois Water Use Act of 1983. While riparian rights are the foundation, the state retains authority to manage water resources for the public good, especially during times of scarcity or for environmental protection. The concept of “beneficial use” is central to water allocation, ensuring that water is used efficiently and without waste. The Illinois Department of Natural Resources (IDNR) also has significant oversight, particularly concerning water resources and permitting for certain water uses, including groundwater appropriations and surface water diversions. When considering conflicts, the courts often balance the needs of different users and the impact on the water body itself. The Public Water Supply Program, administered by the Illinois Department of Public Health (IDPH), focuses on ensuring the safety and potability of public water sources, which indirectly impacts water availability and management strategies. The question revolves around the primary legal framework governing surface water use for a riparian landowner in Illinois.

The Illinois Water Use Act of 1983, codified at 45 ILCS 100/1 et seq., establishes a framework for water use management, particularly for high-capacity wells. A “high-capacity well” is defined as a well capable of yielding more than 100 gallons per minute. The Act requires registration of such wells with the Illinois Department of Natural Resources (IDNR). The core principle of the Act is the prevention of unreasonable depletion of the state’s groundwater resources. This is achieved through a permit system for new high-capacity wells and the registration of existing ones. The Act also addresses potential conflicts arising from water use, encouraging cooperation and the development of local water management plans. The concept of “unreasonable depletion” is central, implying that water use must be sustainable and not cause significant harm to other users or the aquifer’s long-term viability. The IDNR plays a crucial role in administering the Act, including the issuance of permits, monitoring water use, and enforcing its provisions. The Act does not, however, create a system of prior appropriation like some western states; rather, it builds upon the common law doctrine of reasonable use, which is modified by the statutory requirements for high-capacity wells. The Act’s provisions are particularly relevant in areas experiencing groundwater stress or where significant new water demands are anticipated.

In Illinois, the legal framework for water rights is primarily governed by the doctrine of riparian rights, modified by the state’s statutory provisions and common law interpretations. Riparian rights are appurtenant to land that borders a natural body of water. Under this doctrine, landowners whose property abuts a stream or lake have the right to make reasonable use of the water. This reasonableness is a key factor, meaning that a riparian owner cannot use the water in a way that unreasonably interferes with the use by other riparian owners. Factors considered in determining reasonableness include the character of the use, its extent, its suitability to the locality, and the necessity of the use. The Illinois Water Use Act of 1983 (45 ILCS 85/) establishes a permit system for large-volume water withdrawals, requiring permits for withdrawals exceeding a specified daily average from any source within a 30-day period. This act aims to manage water resources more effectively and prevent over-extraction, particularly during periods of water scarcity. It does not abolish riparian rights but supplements them by introducing a regulatory layer for significant withdrawals, ensuring a more balanced approach to water allocation and conservation. The Illinois Department of Natural Resources (IDNR) is the agency responsible for administering this permit program. The concept of prior appropriation, common in western states, is generally not applied in Illinois, where the riparian doctrine prevails. This means that the first person to use the water does not automatically gain superior rights over subsequent users. Instead, all riparian owners share correlative rights to the water, subject to the reasonableness of their use.

The Illinois Water Use Act of 1983, specifically Section 8 (70 ILCS 405/8), addresses the rights of existing permit holders when a new permit application is filed. If a new application is submitted for a water source that is already subject to existing permits, the new applicant must demonstrate that the proposed use will not unreasonably interfere with or impair existing uses authorized by permits issued under this Act. This involves a careful assessment of the potential impact on the water source and the rights of existing users. The Act prioritizes existing, legally established water uses. Therefore, any new appropriation must be evaluated against its potential to negatively affect those already holding permits for that same water source. This principle underpins the regulatory framework for water allocation in Illinois, ensuring a degree of certainty and protection for established water rights. The core concept is to prevent new appropriations from diminishing the quantity or quality of water available to existing permit holders to an extent that constitutes unreasonable interference.