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Chapter 11 - Surface Water Environment Publication 584 2010 Edition CHAPTER 11 Chapter 11 - Surface Water Environment Publication 584 2010 Edition CHAPTER 11 SURFACE WATER ENVIRONMENT 11.0 INTRODUCTION A. Introduction. This chapter provides the designer with an overview of the surface waters and how these resources may be affected by roadway development. Publication 325, Wetland Resources Handbook provides design and environmental professionals with additional details for the identification, regulation, and design of wetland resources in relation to roadway development. This chapter also encourages a team approach in evaluating the effects of highway construction on surface waters. In general, the designer's role is to determine the hydrology and hydraulic related highway effects and significance on sensitive surface waters. B. Purpose. The purpose of this Chapter is to provide the background and regulatory framework for what is required when highway projects may affect surface waters, wetlands and/or groundwater. Due to the complex and controversial nature of surface water environmental engineering, this chapter will address only the simpler, more reliable and accepted engineering practices. Other, more complex practices may be briefly noted, but only to provide background and suggest possible analytical courses of action. In general, PennDOT believes that the subjects and practices provided in this chapter will address 90% or more of the surface water environmental problems encountered by the designer. Other subjects and practices may be added when the need arises. It is imperative that the designer recognize and impress on others that all the practices presented or alluded to in this chapter are not routinely employed on all highway projects or sites. In reality, rarely would more than one or two practices be needed, and then only on selected projects or at unique sites. The methods and practices employed must be approved by the District Project Manager and Environmental Manager in response to specific concerns of the appropriate resource and regulatory agency(ies). C. Surface Waters. Natural surface waters addressed by this chapter are considered "Waters of the Commonwealth" and include: • Streams or rivers. • Ponds, lakes and reservoirs. • Wetlands. • Springs. Not addressed in this chapter are groundwaters such as: • Underground streams or rivers. • Underground ponds or lakes and aquifers. D. Sensitive Surface Waters. In general, the primary factors that may make surface waters sensitive are: • Chemical • Physical • Biological • Regulatory The identification of sensitive waters will be made by the resource agencies with concurrence by PennDOT. Sensitive waters may require additional assessment and/or protection and will generally include waters classified as Exceptional Value (EV), High Quality (HQ), Class A Wild Trout Streams, Stream Sections that Support Natural Reproduction of Trout, and Wilderness Trout Streams. The classification of waters in Pennsylvania is under the jurisdiction of the Pennsylvania Department of Environmental Protection (PA DEP) and Pennsylvania Fish and Boat Commission (PFBC). The following links provide relevant information on the classification of surface waters in the Commonwealth: 11 - 1 Chapter 11 - Surface Water Environment Publication 584 2010 Edition • www.pacode.com/secure/data/025/chapter93/chap93toc.html • sites.state.pa.us/PA_Exec/Fish_Boat/waters_trout.htm E. Functional Values. The functional value of a surface water includes such elements as: • Flood control. • Terrestrial wildlife habitat. • Aquatic habitat. • Groundwater recharge. • Aesthetics. • Shore and bank line geometry. • Water temperature. • Scenic and wild rivers designation. • Endangered species habitat. • Contaminant abatement. • Recreation. A surface water's functional value depends on the interrelationship of key factors including: • Geographic location. • Hydrology. • Climatology. • Geometric setting. • Size. • Quality. • Classification (see Section 11.0.D). • Biotic region. F. Effect and Significance. Determining a surface water effect can determine if a threshold value has been exceeded and if there is a reversible effect. 1. Effect. This is what occurs to the surface waters as a direct or indirect result of the highway improvement. 2. Significance. Significance should be determined by relating an effect to such elements as risk (probability or frequency of occurrence) and cost. Included in such determinations should be any past or future cumulative effects that were either caused by, or expected to be caused by, PennDOT or others. Where practicable and useful, a simple comparison should be made of three conditions: • Existing (pre-construction). • During construction. • Expected post-construction. This comparison is used to identify net changes expected as a result of the project. G. Reversible Effects. It may be necessary to assess whether an effect is reversible or irreversible. Given enough time and resources, surface water effects caused by highway improvements can usually be reversed. Whether the reversal of an effect would be considered as practicable is the context within which PennDOT should address this issue. H. Practicable. In coordination with the applicable resource and regulatory agency(ies), the choices and alternatives may be contingent upon what is practicable. For the purpose of this chapter, practicable shall mean "available and capable of being done after taking into consideration cost, existing technology and logistics in light of overall project purposes." 11 - 2 Chapter 11 - Surface Water Environment Publication 584 2010 Edition This is the definition used in the Memorandum of Agreement (MOA) between the U.S. Environmental Protection Agency (USEPA) and the U.S. Army Corps of Engineers (USACE) (USEPA and USACE, 1990). I. Design Alternatives. When it is determined that highway construction and/or operation activities will have an adverse effect on surface water resources, design alternatives should be considered. There are three general design alternatives that should be considered as applicable: • Avoidance • Minimization. • Compensatory mitigation. 1. Avoidance. Wherever practicable, avoiding the surface water impact is the best and thus the preferred alternative. It should be demonstrated to the applicable resource and regulatory agency(ies) that this alternative is not practicable before any other alternative can be considered. 2. Minimization. Where surface water disturbances cannot be avoided, such disturbances may be minimized through adjustments in the highway's: • Alignment. • Profile. • Template. • Other geometry. The intent is to reduce the impacts to surface water resources when avoidance is not practicable. This may require project down-scoping or reduction of the highway design standards from "desirable" to "acceptable" levels if applicable. 3. Compensatory Mitigation. When required through coordination with the applicable resource and regulatory agency(ies) and approved by the District Project Manager and Environmental Manager, PennDOT will undertake compensatory mitigation measures to offset the adverse effects of highway development on surface water resources. Compensatory mitigation may include on-site mitigation, off-site mitigation, in-kind mitigation, out-of-kind mitigation, or monetary compensation. 11.1 POLICY A. Introduction. Set forth in this section are PennDOT's guidelines for highway construction affecting sensitive surface waters. These address: • Rules and regulations. • Cost effectiveness. • Analysis/assessment of complexity. • Upgrading functional values. • Environmental studies. • Surface water assessment. • Surface water analysis. • Permits and certifications. B. Rules and Regulations. All surface water design, construction and maintenance must be in compliance with Federal, State and Municipal laws, regulations, executive orders and Memorandums of Agreement (MOAs) and Understanding (MOUs). The principal laws, regulations and executive orders applicable to this chapter are as follows: 1. Federal. These are as follows: 11 - 3 Chapter 11 - Surface Water Environment Publication 584 2010 Edition • Clean Water Act (33 USC 1251 -1376, DOT Order 5660.1A, FHWA Notices N5000.3 and 5000.4, 23 CFR 650, Subpart B, E, 33 CFR 209, 40 CFR 120). • National Environmental Policy Act (NEPA) (FHWA 23 CFR 771) • Protection of Wetlands (Executive Order 11990, 23 CFR 777). • Floodplain Management (Executive Order 11988 (23 CFR 650, Subpart A, 23 CFR 771), amended by Executive Order 12148, DOT Order 5650.2). 2. State. These are as follows: • Dam Safety and Encroachment Act (32 P.S. §§ 693.1-693.27). • The Clean Streams Law (35 P.S. §§ 691.1-691.1001). • Floodplain Management Act (32 P.S. §§ 679.101-679.601). 3. Municipal and County. These are as follows: • Section 1905-A, Commonwealth Administrative Code, amended Act 14. • Municipal Planning Code, Acts 67 and 68. C. Cost Effectiveness. It is recognized that costs associated with surface water environmental engineering may not be reliably quantified - commonly those associated with the functional values of a resource. Nevertheless, it is important that any mitigation be both: • Cost effective. • Demonstrably beneficial. D. Enhancing Functional Values. In general, it is the intent of PennDOT to maintain the existing functional values of surface waters. Where cost-effective benefits can be demonstrated, existing functional values will be enhanced consistent with PennDOT and FHWA environmental stewardship policies. Examples of some benefits are: • Watershed enhancement. • Wetland and stream banking. • Acceptable
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