Stream Buffers

This model ordinance establishes minimum requirements for vegetated buffers along streams to protect water quality, stabilize stream banks, and preserve aquatic and riparian habitat. The ordinance creates a framework for requiring, designing, and maintaining these buffers during and after land development. Its provisions are intended to mitigate the impacts of non-point source pollution, reduce erosion and sedimentation, and maintain the chemical, physical, and biological integrity of a jurisdiction’s water resources.

The model is structured around a three-zone buffer system that provides layered protection for the stream ecosystem. It includes standards for a minimum base buffer width that expands to include adjacent sensitive features like steep slopes, wetlands, and floodplains. The ordinance provides comprehensive language covering applicability, plan submission requirements, permitted and restricted uses, long-term maintenance, enforcement procedures, and variance criteria. While this model focuses on forested buffers, its principles can be adapted for other vegetative communities, such as those found in the Napa County Stream Buffers ordinance.

Key provisions

This model ordinance contains detailed standards for the application, design, management, and enforcement of stream buffers.

Applicability

The ordinance applies to all proposed development, timber harvesting, and surface mining operations within the jurisdiction. It also applies to any existing parcel or activity found to be causing pollution, erosion, or habitat degradation. Certain exemptions are provided, including:

• Agricultural operations covered by an approved Natural Resources Conservation Service (NRCS) conservation plan.
• Timber harvesting operations with an approved forest management plan.
• Active surface mining operations with an approved state or federal permit.
• Development projects that had received specific prior approvals (e.g., a valid building permit or recorded plat) before the ordinance effective date.

Buffer Widths and Design Standards

The core of the ordinance is a multi-layered approach to determining buffer width based on site-specific conditions. The buffer begins at the edge of the stream bank of the active channel.

The minimum base width for all forest buffers is 100 feet. This base width must be expanded to include any of the following contiguous sensitive areas:

• Stream Order: For third-order and higher streams, an additional 25 feet is added to the base width.
• 100-Year Floodplain: The buffer must extend to encompass the entire 100-year floodplain, plus a minimum of 25 feet beyond the floodplain edge.
• Wetlands: Where wetlands are adjacent to the stream, the buffer must include the full extent of the wetland plus a 25-foot zone beyond its delineated edge. This approach complements dedicated Wetlands Protection regulations.
• Steep Slopes: The buffer width is increased where steep slopes drain into the stream system. The model provides several methods for this adjustment. One example is a fixed-width addition based on percent slope:

The Three-Zone Buffer System

The total buffer area is managed as three distinct zones, each with specific functions, restrictions, and vegetative targets.

1. Zone 1: Streamside Zone. This zone’s primary function is to protect the physical and ecological integrity of the stream. It begins at the top of the stream bank and extends a minimum of 25 feet. Uses are highly restricted to essential crossings and flood control structures. The vegetative target is undisturbed native vegetation.
2. Zone 2: Middle Zone. This zone provides distance between development and the sensitive streamside zone. It begins at the outer edge of Zone 1 and extends a minimum of 50 feet, plus any additional width required for slopes or other features. Allowable uses include recreational paths and, with approval, stormwater management facilities. The vegetative target is mature native vegetation.
3. Zone 3: Outer Zone. This zone acts as a final filter for runoff and prevents encroachment from developed areas. It provides a 25-foot setback between the Middle Zone and the nearest permanent structure. No permanent structures, impervious cover (except paths), or septic systems are permitted.

Setbacks for Pollution Hazards

The ordinance designates certain land uses as potential water pollution hazards and requires specific minimum setbacks from any stream or waterbody, independent of the buffer width. These include:

• Septic system drainfields: 100 feet
• Storage of hazardous substances: 150 feet
• Petroleum storage facilities: 150 feet
• Confined animal feedlots: 250 feet
• Solid waste landfills or junkyards: 300 feet

Plan Submittal and Permitting

Applicants for development, timber harvesting, or mining permits must submit a detailed buffer plan. The plan must include maps (e.g., at 1″=50′ scale) showing field-delineated streams and wetlands, the 100-year floodplain, hydric soils, steep slopes, and existing vegetation. The approved buffer must be clearly delineated on the final grading plan, and permanent boundary markers must be installed at the edge of the Middle Zone before final plan approval.

Buffer Management and Maintenance

The ordinance establishes strict limitations on activities within Zones 1 and 2 of the buffer. Prohibited activities include clearing vegetation, grading, filling or dumping, and operating motorized vehicles, except with agency approval for permitted uses. Permitted uses, such as road or utility crossings, require an analysis showing no feasible alternative exists and must be designed to minimize impact (e.g., perpendicular crossings).

Stormwater management facilities may be permitted in the Middle Zone if they are necessary and non-structural alternatives are not feasible. Their design must follow criteria in the jurisdiction’s official Design Manual. For long-term protection, all final plats must show the buffer boundaries and include notes restricting disturbance. A declaration of protective covenant, recorded in the land records, is required to ensure the buffer is preserved in perpetuity.

Enforcement and Penalties

The director of the responsible agency is empowered to enforce the ordinance through a formal process of correction notices and citations. Violations can result in significant penalties, including:

• Civil penalties up to $1,000 for each day of violation.
• Criminal penalties including fines up to $1,000 and/or imprisonment.
• Liability for restoration costs, potentially equal to twice the cost of restoring the buffer.

Selected provisions, annotated

The forest buffer shall be composed of three distinct zones, with each zone having its own set of allowable uses and vegetative targets as specified in this ordinance.

Model Stream Buffer Ordinance, Section VI.E

This provision establishes the three-zone system, which is a key strength of the model. By creating distinct zones with increasing restrictions closer to the stream, the ordinance provides layered, targeted protection. This structure allows for limited, low-impact uses in the outer areas while preserving the most critical streamside area in an undisturbed state.

The forest buffer width shall be adjusted to include contiguous sensitive areas, such as steep slopes or erodible soils, where development or disturbance may adversely affect water quality, streams, wetlands, or other waterbodies.

Model Stream Buffer Ordinance, Section VI.A

This clause mandates an adaptive buffer width, moving beyond a simple fixed-width requirement. It recognizes that a uniform buffer is not equally effective in all landscapes. By expanding the buffer to incorporate site-specific hazards like steep slopes, the ordinance ensures a higher level of protection where the risk of erosion and polluted runoff is greatest.

All forest buffer areas shall be maintained through a declaration of protective covenant, which is required to be submitted for approval… The covenant shall be recorded in the land records and shall run with the land and continue in perpetuity.

Model Stream Buffer Ordinance, Section VII.D

This requirement provides the legal mechanism for permanent buffer protection. A protective covenant is a legally binding agreement tied to the property deed, ensuring that restrictions on buffer use and disturbance remain in force even after the property is sold. This is critical for preventing the degradation of buffers over the long term.

Where the standards and management requirements of this buffer ordinance are in conflict with other laws, regulations, and policies… the more restrictive shall apply.

Model Stream Buffer Ordinance, Section X

This is a standard but essential legal provision for any environmental regulation. It ensures that the ordinance does not inadvertently weaken other existing protections. If another regulation (e.g., a state-level wetland rule or a local floodplain ordinance) requires a wider buffer or stricter limitations, that more protective rule will govern.

What makes it a useful model

This ordinance serves as a strong foundation for communities seeking to develop effective stream protection regulations. Its primary strength lies in its comprehensive and technically robust approach. By integrating a three-zone system with adaptive width requirements, it creates a buffer that is tailored to the specific ecological functions and physical risks of the stream corridor. This is a significant improvement over simplistic, fixed-width buffer ordinances that may under-protect sensitive areas or over-regulate less critical ones.

The model is also legally sound, providing clear language for long-term protection through plat notations and permanent protective covenants. These provisions are crucial for ensuring that the buffer’s integrity is maintained long after a development project is completed. Furthermore, the inclusion of detailed sections on plan requirements, permitted uses, enforcement, and variances provides a complete administrative framework that a local government can readily adapt.

Finally, the ordinance is designed for customization. It contains placeholders for local agency names, references to local design manuals, and options for technical standards (such as different methods for slope-based width adjustments). This built-in flexibility allows a municipality to modify the language to fit its unique administrative structure, legal authorities, and environmental priorities, making it a practical tool for a wide range of jurisdictions.

Adaptation checklist for municipalities

Before adopting this model, a municipality must customize its provisions to align with local conditions, administrative structures, and legal requirements. Key adaptation steps include:

• Identify and name the responsible local agency or agencies (e.g., Department of Planning, Department of Environmental Protection) in all relevant sections.
• Adopt or reference official stream maps that define which watercourses (e.g., perennial, intermittent) are subject to the ordinance.
• Review and confirm the base buffer width (100 feet is recommended) and the specific minimum widths for the Streamside, Middle, and Outer Zones.
• Select and codify a specific methodology for expanding buffer widths on steep slopes and other sensitive areas.
• Customize the lists of permitted and restricted uses within each buffer zone to reflect local land use patterns and protection goals.
• Review and amend the list of potential water pollution hazards and their required setback distances based on local risks.
• Establish a fee schedule for buffer plan review, permitting, and inspections.
• Define specific civil and criminal penalty amounts and ensure enforcement procedures are consistent with local and state legal authority.
• Integrate the ordinance with other local environmental regulations, such as those for Erosion and Sediment Control, Forest Conservation, or floodplain management.
• Reference the jurisdiction’s specific stormwater Design Manual for the design of any BMPs permitted within the buffer.
• Develop standardized legal language for the required protective covenants and specifications for the permanent on-site boundary markers.
• Define the specific criteria and administrative process for reviewing and granting variances.