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A protected population is the predominant user of the impacted resource. A protected population uses the resource differently than the population as a whole. Impacted areas and mitigation areas are distributed unequally among populations. The proposed water quality or drainage improvements will affect the visual and aesthetic quality of the project site or sites. In the case where a protected population group is the predominant user of the impacted resource, the group would disproportionately experience any adverse or beneficial effects to the resource. Where the protected population uses the resource differently than the general population, it may be necessary to evaluate impacts based on type of use. A common example would be Native American use of fishery resources for subsistence compared to general population use of the same resources for recreation purposes only. When impacted areas and mitigation areas are distributed unequally among population groups, the problem is similar to many other distribution problems discussed in this guidebook. An example would be reducing flood plain storage in one area and undertaking an offsetting excavation project in another area. The project could differentially affect protected populations depending on their proximity to, and use of, the construction and excavation areas. The potential for water quality and drainage mitigation projects to cause distributive visual and aesthetic effects can be evaluated using methods explained in Chapter 11. The approach we recommend for evaluating impacts due to water quality and drainage improvements involves three steps. Step 1 Identify the scope of the proposed water quality and drainage improvements and alternative improvements based on engineering judgment and the applicable regulations of governing jurisdictions as outlined above. Step 2 Evaluate whether or not the improvements affect protected populations using the checklists outlined below. Step 3 Modify or alter the scope of the proposed improvements as necessary and practical to minimize or eliminate impacts to protected populations. METHODS The methods for assessing likely water quality impacts of a proposed transportation project are summarized in Table 5-3. The methods presented in this chapter are somewhat different in nature than those in most other chapters of this guidebook in that they consist of checklists. The five checklists are intended to raise the salient environmental justice considerations related to water quality when significant changes to the transportation system are contemplated. The checklists are organized to ensure assessment of the following areas: Land acquisition, Visual quality, Accessibility, 126

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Groundwater, and Surface water quality and quantity. These checklists can be used individually or in combination as necessary to evaluate water quality and drainage issues for the project in question. Table 5-3. Summary of methods for analyzing water quality and drainage effects Assessment Appropriate Use Data Expertise Method level uses when needs required 1. Land Screening/ Project/ Land acquisition could Low Records review, acquisition detailed corridor impact or displace protected survey/interview checklist assessment populations 2. Visual Screening/ Project/ Visual quality effects of Low Visual quality quality detailed corridor water quality improvements design and checklist assessment could affect protected communication populations 3. Access- Screening/ Project/ Improvements impair access Low Survey/interview ibility detailed corridor to water resources check-list assessment 4. Groundwater Screening/ Project/ Improvements have the Medium GMS quality detailed corridor potential to affect checklist assessment groundwater quality or quantity 5. Surface Screening/ Project/ Improvements have the Medium HEC-RAS, water detailed corridor potential to affect surface HEC-2, SWMM quality assessment water quality or quantity checklist Checklist 1. Land acquisition Water quality and drainage improvements often require that land be acquired to construct holding ponds, stilling basins, swales, and culverts. Although the locations of these improvements generally are determined by the topographical elevations of the land and the physics of water flow, there may be some flexibility in the siting of improvements. Check for: Does the affected area include protected populations? Suggested approach. Conduct a threshold analysis using the most recent census block and block-group information or more detailed information if it is available from local governments or metropolitan planning organizations (MPOs). Verify findings by conducting a field survey and interviewing persons with local knowledge of the area. Refer to Chapter 2 for more information. Will any of the proposed acquisitions separate members of protected population groups from their homes or other properties? Examples would include minority, low-income, 127

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disabled, elderly, or single female head of household homeowners, tenants or property owners. If the answer is yes, compile a list of the properties and answer the following checklist question. If the answer is no, there are no adverse effects to protected populations. Suggested approach. Perform a records review to identify the property owners and any tenants. Determine if any are members of protected population groups by conducting personal interviews or surveys (see Chapter 2 for a suggested questionnaire). Are there other options or mitigation measures that could be implemented in lieu of displacing persons in protected population groups? If the answer is no for any of the listed properties, review the mitigation techniques and answer the following checklist questions. Mitigation techniques. Consider locating ponds either downstream or upstream of optimal locations if it would mean less impact to affected populations and if water quality/quantity issues would not be overly compromised. Consider alternatives to ponds, including grit chambers, underground detention, or mechanical treatment methods that reduce or eliminate the need for large pond areas and decrease the number and size of necessary land acquisitions. Be aware, however, that the cost of these methods generally is much higher than ponding for an equivalent result. Would the unmitigated acquisition of land owned by members of a protected population or the displacement of homeowners and tenants cause an economic or personal hardship for the affected individuals? If so, consider the following information. Discussion. Such a situation can be avoided in most cases. An exception might occur in highly populated built environments where topography and project design features severely restrict the available options. In such situations, every effort should be made to negotiate fair and reasonable condemnation terms to satisfy property owners. Assistance should be provided to displaced individuals. Because these situations are often very contentious, the responsible agency should take proactive steps to prepare a justification in the event that a formal complaint or lawsuit is filed. Do the unmitigated acquisitions disproportionately impact members of protected population groups? If so, it will be necessary to either alter the project design or justify the action. Discussion. Any evaluation that shows no disproportionate impact may be contested. To prepare for this eventuality, the evaluation should consider the proportion of affected property owners and displaced persons in protected population groups relative to the population proportion in the study area and in comparison areas. See the method for threshold analysis described in Chapter 2 and the related discussion, "Limitations of using comparison thresholds in environmental justice assessment." 128

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Checklist 2. Visual quality Many of the improvements associated with water quality and drainage systems are constructed within the public realm and are highly visible elements of the connection between public transportation infrastructure and the natural environment. Aesthetic design of water quality and drainage improvements can range from functional and utilitarian to highly attractive features that enhance the surrounding built or natural environment. Protected populations should be provided with meaningful public involvement that proactively solicits input and provides access to information concerning aesthetic design improvements. Chapter 11, Visual Quality, provides a much more in-depth analysis of this issue as well as techniques for evaluating visual quality impacts of water quality and drainage improvements. The following checklist can be used to evaluate visual quality effects of water quality and drainage elements. Check for: Is the affected area within the activity space where protected populations live, work, take part in recreational activities, or otherwise spend significant amounts of time? If the answer is yes, go to the following checklist question. If the answer is no, there would be no adverse effects to protected populations. Suggested approach. Use an appropriate combination of the techniques described in Chapter 2 to identify the presence of protected populations. Would the proposed water quality and drainage improvements be visible to members of protected populations? If yes, go to the following checklist question. If no, there would be no visual quality impacts. Suggested approach. As a first step, use GIS or a desktop program to overlay the location of improvements on a map of protected populations. If improvements are located within the activity space of protected populations, consider conducting a field survey or using GIS, as appropriate, to perform a line of sight, view-shed, or some other type of visibility analysis. Perform a visual quality assessment. Do results of the assessment indicate that visual quality would be adversely affected? If so, go to the following checklist question. Suggested approach. Perform an appropriate visual quality assessment. Techniques appropriate for identifying visual quality impacts to affected populations are provided in Chapter 11. What are the most appropriate mitigation measures to alleviate adverse effects? Mitigation techniques. General aesthetic: Consider incorporating a high level of aesthetic into the visible or exposed portion of water quality and drainage improvements, thus making them an amenity to the community instead of a detriment. Consideration should be given to making the improvements blend with the natural landscape. 129

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Recreation opportunities: Consider incorporating trails for recreation and basic transportation around and through the improvement areas. Interpretation and education opportunities: Consider providing interpretation of the water quality improvements via signage (multilingual as appropriate) for educational purposes. Checklist 3. Accessibility Transportation improvements, including roadway widening or access control, and their associated storm water ponds, culverts, and channels may eliminate public access to natural water bodies and may adversely affect protected populations. Chapter 7, Transportation User Effects, goes into greater detail about how to evaluate accessibility. The following are some ideas specifically related to water quality and drainage. Check for: Is there existing recreational access and use of water bodies in the project area for activities such as fishing or swimming? Be sure to ascertain whether specific population groups use the water bodies differently than the general population. Suggested approach. Generate a list of the water bodies in the affected areas. Using expert knowledge, determine if any of the water bodies are used for recreational purposes. Review the list and findings with members of protected population groups through interviews, public meetings, focus groups, surveys, or some other form of feedback. Will the proposed water quality or drainage improvements reduce accessibility to water bodies used for recreation or reduce the level of safety in traveling to or using the water bodies? If so, consider appropriate mitigation techniques. Mitigation techniques. Consider as part of the project providing alternative access for fishing, swimming, or other recreational uses. An example would be a publicly accessible pier or dock in a safe location that does not compromise the safety improvements included with the roadway or the water quality and drainage improvements. Dual-purpose improvements could be considered, such as designing access bridges or trails for maintenance of outlet structures to also accommodate public use. Are there any safety issues associated with the proposed water quality or drainage improvements? Consider issues such as whether the area is near parks, day care centers, residences, or other areas where children play. If so, consider appropriate mitigation techniques. Mitigation techniques. Consider the use of fencing to protect people from potentially dangerous intake structures or other dangerous drops. Fencing may also be considered around ponds, although it may detract from the overall aesthetic of the area. 130

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Consider grading the site to provide gentle slopes around ponds (3:1 to 5:1) to reduce chances of children falling into water. Plantings and landscaping treatments such as boulders and thorny shrubs improve aesthetics and tend to keep curious children and adults a safe distance away from ponding areas. Rescue items such as boards for thin ice rescue or life rings and rope may be placed near the pond and marked for emergency use only. Structures with pipes large enough to crawl or walk in should include fencing or gates with locks to prevent the public from entering, while allowing access for maintenance personnel. Checklist 4. Groundwater quality and quantity Transportation improvements often involve excavating and filling areas of the natural landscape. Drainage improvements typically require underground pipes several feet below the roadway and the construction of drainage basins at or near the existing water table. The environmental analysis should consider whether or not potential impacts to groundwater--such as lowering the groundwater elevations in a localized area--will adversely impact protected populations. Check for: Are shallow private wells being used for domestic use? Some protected populations are more likely to lack the economic means to construct deep wells for domestic water use, and therefore are more likely to experience the adverse effects of changes to shallow groundwater elevations in their area. Is there an interface between groundwater and surface water in the project area, such as springs and water falls? In areas where groundwater and surface water meet, any impacts to groundwater elevations could have significant impacts on surface water features. Such impacts could adversely affect protected populations because they may be more likely to utilize the surface water for domestic use or may value the resource more highly than other population groups. Does the affected area encompass any historic settlements? Many historic settlements and indigenous people's camps were built around natural springs; it is common for historic sites to be located at such locations. If any of these situations exist in the study area, determine if there are impacts to protected populations using techniques described in Chapter 2. In the case of such impacts, consider the following mitigation techniques: Reconsider roadway and drainage design to minimize effects to groundwater. Strategies may include the following: Raising roadway grades and pond elevations. Designing ponds that are larger and flatter rather than deeper with smaller areas. 131

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Designing ponds to infiltrate water back into the ground, and thus assure no net loss to the groundwater balance. Taking measures to seal joints of deep sewer pipes to minimize infiltration of groundwater into the pipes and drainage system: Pumpable grouts can be the most cost effective and Trenchless lining of pipes with cured-in-place lining systems may also be considered. Isolate the roadbed from the groundwater table with concrete, clay, or a geotextile lining system. Provide potable water supplies to homes by extending the local water distribution network if feasible. If no water distribution network exists, consider drilling deeper wells for the affected properties. Recreate water flow for springs and waterfalls using mechanical means such as pumping or municipal water systems. This option is only feasible for low-volume flows and short water falls. The construction of a mechanical system may not be possible without causing temporary damage to the natural water feature and thus may defeat its own purpose. Checklist 5. Surface water quality and quantity Transportation improvements nearly always affect the surface water quality and quantity of the surrounding area. Drainage improvements are included with transportation projects to convey storm water away from the roadway and toward the natural water body. Such improvements typically involve underground pipes, ditches and the construction of drainage basins to conduct, store and treat surface water. These improvements often result in modifications to the physical shape, size, or dynamic characteristics of existing streams or ponds (i.e., water movement that is faster, slower, higher, or lower). The environmental analysis should consider whether or not the potential impacts to surface water quality caused by raising high water elevations in a localized area would adversely impact protected populations. Examples include increasing groundwater flows and subsequent erosion problems. Check for: Does the area include existing surface water elements such as lakes, streams, rivers, or wetlands that will be affected by the improvements? Connections to such surface water features should automatically qualify for additional analysis. Also consider if existing surface water that currently runs to natural water bodies will be diverted elsewhere, thus reducing the natural recharge of those water bodies. Suggested approach. If any of these situations exist in the study area, identify any impacts to protected populations using techniques described in Chapter 2. If so, consider the following mitigation techniques. 132