NATIONAL PARK SERVICE 

CHAPTER 4.0 ENVIRONMENTAL CONSEQUENCES 

 

This chapter describes the potential environmental impacts of the two management alternatives 

prepared for Great Falls Park. As discussed in Chapter 2 of this document, these are: 

y Alternative A – Status Quo/Continuation of Current Conditions 

y Alternative B – Preferred Alternative 

 

The resource areas assessed in the analysis of environmental consequences were identified 

based on legislative requirements, resource knowledge and information, and concerns identified 

by the public and governmental agencies during scoping. 

Environmental Consequences discussed in this GMP/EIS are formatted in accordance with the 

NPS Director’s Order 12 – NEPA Policy Manual. Since the EIS considers management 

alternatives, many of the potential impacts to individual resource areas are common to both 

alternatives. These are identified in the environmental consequences discussion. 

The discussion in this chapter follows the “tiered” approach recommended in 40 C.F.R. Section 

1502.14 that encourages agencies to tier their EISs, working from broad, general NEPA 

environmental impact analysis documents to more site-specific ones in decision making. The 

Great Falls Park GMP/EIS is a large-scale plan that identifies a broad direction. Therefore, 

some of the discussions in this chapter are generalized. In the future, additional environmental 

analysis may be conducted pursuant to NEPA, in instances where a specific action or activity, 

consistent with the goals and objectives of the GMP/EIS, is proposed. 

This section also presents analyses of potential cumulative impacts that could result from a 

proposed action when considered together with any reasonably foreseeable projects that may 

affect the natural and human environment in the study area. 
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GREAT FALLS PARK, VIRGINIA y FINAL GMP/EIS 4.2

 4.1 ALTERNATIVE A – STATUS QUO/CONTINUE CURRENT CONDITIONS 

 

This section of the document identifies potential impacts on resources that could result under 

Alternative A (Continue Current Conditions). 

 

4.1.1 Impacts on Land Use and Socio-Economic Conditions 

Land Use, Property Boundaries, and Land Protection

Under Alternative A, there would be no impacts to the surrounding uses. Land uses within the 

park would continue to function similar to existing conditions. 

There are no boundary changes proposed under Alternative A. In the future, the park may 

undertake establishing a revised boundary based on the criteria identified in Chapter 2 of this 

document. At that time, in accordance with NEPA, the park may undertake additional 

environmental analysis to determine impacts resulting from the boundary change. 

Establishing boundaries does not necessarily constitute a proposal to purchase the land within 

those boundaries. A variety of land protection methods are available within the authorized 

boundaries of the park units. In addition to fee simple acquisition, scenic, conservation, and 

access easements might be acquired, or local zoning and cooperative planning and management 

could be employed. 

Visitation and Visitor Activities

 

Under Alternative A, there would be no changes to visitation in the short-term. In the longterm, the projected growth in the region, including Fairfax and Montgomery Counties, would 

likely result in increasing the number of visitors to the park. Currently, the availability of 

parking is the biggest determinant to the number of people who can visit the park at a given 

time. This condition is not anticipated to change in the future, since a majority of visitors to the 

park would visit in a vehicle. Under existing conditions, visitors experience delays entering the 

park on an average of 10 to 15 times per year. Technological improvements at the entrance 

station are anticipated to alleviate some of this delay. If visitation increases considerably in the 

future, there may be additional days when delays are experienced along Old Dominion Drive 

and potentially Georgetown Pike, resulting in an adverse impact to visitation. 

Connecting the park to regional trails could mitigate some of this potential pressure, since 

visitors could access the park via non-motorized modes of transportation. However, depending 

on the increase in visitation demand, NPS could explore alternative means of providing access 

to the park in the future, including connecting Great Falls Park to a potential regional shuttle 

system. 

Connecting the park to regional trails would also provide visitors additional recreational 

opportunities. Visitors could arrive at the park on these trails, or start at the park and explore 

the larger region. The additional recreational opportunities would result in a positive impact on 

visitor experience. 
ENVIRONMENTAL CONSEQUENCES 

4.3 NATIONAL PARK SERVICE 

In addition, the following measures would result in potential impacts on the experience of 

visitors to the park as described: 

• Improve visitor center to enhance its appearance including the courtyard, use interior 

space more efficiently, modify one of the entrance ramps to meet ADA requirements, 

rehabilitate existing restroom facilities at the visitor center and comfort facility: During 

renovations to the visitor center and comfort facility, there would be minor, short-term 

adverse impacts on visitor experience of these facilities. However, over the long-term, 

once these renovations are completed, visitors would benefit from the improved 

facilities. 

• Improve signage to identify allowable uses on trails: This improvement would help with 

visitor orientation as well as reduce conflicts between various user groups on the park’s 

trail system. Provided these signs are designed to ensure that they are compatible with 

the park’s natural condition and do not add visual clutter, this measure would result in a 

positive impact on visitor experience at the park. 

Community Facilities - Police, Fire, and Rescue Services

Under Alternative A, during vehicular traffic back-ups along Old Dominion Drive, police, fire, 

and rescue services would continue to experience delays in accessing the park during 

emergencies. Technological improvements at the entrance station are anticipated to alleviate 

some of the delay and could improve emergency access. 

Neighboring Population and Socio-Economic Conditions

 

The socio-economic characteristics of the area surrounding the park primarily includes 

established residential communities, with institutions interspersed within. Changes in the 

management and operations of the park in accordance with Alternative A are not anticipated to 

result in a change in population characteristics in the study area, or result in the addition or 

elimination of large number of jobs. Therefore, impacts anticipated on the neighboring 

population and socio-economic conditions would be negligible under the Alternative A. 

Cumulative Impacts

 

Under Alternative A, no cumulative land use and socio-economic impacts are anticipated. 

Conclusion

Under Alternative A, there would be temporary and short-term impacts on land use resources, 

including visitation and visitor activities, which would be related to renovation activities. Over 

the long-term, the proposed measures are anticipated to result in positive impacts as park 

facilities would be improved consistent with NPS management policies. Also, in the long-term, 

increasing growth in the region could result in increasing visitor demand at the park. Since there 

is no proposal to increase parking within the park, added demand could increase the number of 

times when visitors experience delays in accessing the park. While technological improvements 

at the entrance station and connection to regional trails is anticipated to reduce the number of 
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GREAT FALLS PARK, VIRGINIA y FINAL GMP/EIS 4.4

times visitors experience delays in entering the park, the park would consider new measures, if 

delays to enter the park do increase due to increased demand in the future. 

The proposed measures would not impact the socio-economic characteristics of the 

neighboring areas, nor are there any adverse impacts anticipated from boundary changes based 

on the criteria that would be used to acquire more land. Therefore, there would be no 

impairment of land use and socio-economic resources under Alternative A. 

 

4.1.2 Impacts on Cultural Resources 

 

Archaeological and Historic Resources

 

Their potential impacts on cultural resources within the park would be as follows: 

• Develop an Integrated Resource Management Plan (IRMP) to protect sensitive cultural 

resources from potential vegetation damage and adopt best management practices 

(BMP) to protect cultural resources that are either listed, or eligible for listing, on the 

National Register: These measures are anticipated to result in a beneficial impact since 

the IRMP and BMPs would seek to minimize potential damage from trees and other 

vegetation on cultural resources, including the Patowmack Canal and Matildaville. 

• Provide additional protection to natural and cultural resources by implementing 

practices such as fences adjacent to trails to reduce conflicts with visitors: These 

measures would result in a positive impact on archaeological and historical resources in 

the park. Visitors would be guided away from sensitive areas due to addition of 

protection measures in areas where trails conflict with natural and cultural resources. 

• Evaluate existing undesignated trails and eliminate those that adversely impact natural or 

cultural resources: Eliminating undesignated trails in areas of conflict with cultural 

resources would result in a positive impact. 

The use of trails for horseback riding in the vicinity of sensitive resources (such as along 

Matildaville Trail in the vicinity of the Matildaville ruins) would continue the potential for 

damage to these resources. Also, in the future, connecting to the regional trail network would 

increase the usage of trails within the park. Increased usage would increase the potential for 

damage to sensitive cultural resources such as the historic road traces that comprise some of the 

trail routes. 

Viewsheds

 

Under Alternative A, there would be no changes to existing viewsheds. 

Cumulative Impacts

 

Under Alternative A, no cumulative impacts on cultural resources are anticipated. 
ENVIRONMENTAL CONSEQUENCES 

4.5 NATIONAL PARK SERVICE 

Conclusion

The measures proposed under Alternative A are anticipated to benefit the protection and 

preservation of cultural resources within the park, consistent with NPS management policies. 

However, the continued use of portions of existing trails that are either part of sensitive 

resources or adjacent to such resources would continue the potential for impairment of these 

resources. 

4.1.3 Impacts on Natural Resources 

Their potential impacts on natural resources within the park would be as described below: 

Geophysical Resources

Under Alternative A, no impacts are anticipated on geophysical resources. 

Water Resources

 

Under Alternative A, there would be no new impacts on water resources. The lower level of the 

visitor center and the two northern parking lots would continue to function within the 100-year 

floodplain, similar to existing conditions. The potential for flooding at the lower level of the 

visitor center, that includes staff offices and the food concession stand, would continue. 

Also, trail erosion would continue due to regular use, and could impact surface and ground 

water resources. This would include the use of trails for horseback riding in the vicinity of 

sensitive water resources (such as near Clay Pond). In addition, in the future, connecting to the 

regional trail network would increase the usage of trails within the park. Increased usage would 

increase the potential for damage to sensitive natural resources such as the Difficult Run and 

Mine Run. To minimize potential impacts, the park would continue to monitor trails and make 

necessary repairs. 

Biological Resources

Under Alternative A, the following measures would affect biological resources in the park: 

• Develop an Integrated Resource Management Plan (IRMP) to protect sensitive cultural 

resources from potential vegetation damage and adopt BMPs to protect cultural 

resources, especially those that are listed on the National Register: An IRMP and BMPs 

are typically developed to reduce or eliminate potential environmental impacts. During 

the preparation of the IRMP and BMPs, the park would seek to protect sensitive cultural 

resources without adversely impacting biological resources. Therefore, this measure is 

not anticipated to result in an adverse impact. 

• Provide additional protection to natural and cultural resources by reducing conflicts 

with users on trails: Such measures would reduce potential damage to natural resources 

(such as the rare species in terrace communities along the River Trail) by focusing on 

resource protection, and are anticipated to result in a positive impact on biological 

resources. 
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GREAT FALLS PARK, VIRGINIA y FINAL GMP/EIS 4.6

• Evaluate existing undesignated trails and eliminate those that adversely impact natural or 

cultural resources: Eliminating undesignated trails in areas of conflict with natural 

resources would result in a positive impact. 

Air Quality

• Introduce technology that expedites payment and other operational functions at the 

entrance station: This measure would result in a negligible benefit to local air quality. 

Technological improvements are anticipated to result in an improved rate of traffic flow 

at the entrance station, which would reduce vehicle queues and localized engine idlingrelated vehicular emissions. 

Noise Levels

Under Alternative A, there would be temporary construction-related noise generated during the 

renovation of the visitor center and maintenance facility, the impact of which would be 

negligible. 

Cumulative Impacts

 

Under Alternative A, the anticipated growth in the region’s population could result in increased 

visitation to the park. This could result in a considerable increase in vehicles waiting to access 

the park, resulting in a minor adverse impact on localized air quality. Also, the existing natural 

habitats within the park could be further burdened if the area around the park is developed in 

response to some of this anticipated regional growth. 

 

Conclusion

Under Alternative A, there would be potential positive impacts to natural resources due to the 

proposed elimination of undesignated trails in areas where these conflict with sensitive 

resources. However, the continued use of portions of existing trails that are adjacent to 

sensitive resources would continue the potential for impairment of these resources. Also, the 

anticipated population growth in the region has the potential to result in a minor adverse impact 

on localized air quality, as well as burden the natural habitats within the park. Depending upon 

the pressures that may be experienced due to regional growth, the park would address this issue 

further in the future. 
ENVIRONMENTAL CONSEQUENCES 

4.7 NATIONAL PARK SERVICE 

4.1.4 Impacts on Transportation Systems 

 

Vehicular Access

The following actions are aimed to support these policies. Their potential impacts on 

transportation systems within and adjacent to the park would be as follows: 

• Introduce technology that expedites payment and other operational functions at the 

entrance station: Potential technological improvements, such as where pass holders 

would swipe their cards to gain access, are anticipated to increase the processing rate, 

and reduce the waiting time at the gate for all visitors. Provided the parking lots are not 

full, queues that currently form during peak arrival periods would be reduced or 

potentially eliminated. This would result in a positive impact on visitor access to the 

park. 

• During severe crowding, initiate a one vehicle out, one vehicle in policy: When this 

occurs, visitors waiting in line would be informed to expect delays. Vehicle crowding 

would continue to result in a minor adverse impact on visitor access to the park. 

 

Parking

Under Alternative A, there would be no change to existing parking conditions. Long delays and 

large queues that are experienced on peak days would continue when the parking lots are full. 

These delays and queues could be more frequent than the current 10 to 15 times per year, if 

visitor demand increases in the future. Access to homes along Old Dominion Drive would 

continue to be blocked during these conditions on peak days. Also, visitors arriving after the 

lots fill would continue to wait in the queue along Old Dominion Drive due to the one vehicle 

out, one vehicle in policy and the lack of locations to turn around. 

Cumulative Impacts

 

Over the long-term, the projected growth in the region could increase visitation to the park. 

This could result in additional days when delays are experienced along Old Dominion Drive and 

potentially Georgetown Pike, resulting in a minor adverse impact on the area’s transportation 

systems. 

 

Conclusion

Under Alternative A, the one vehicle out, one vehicle in policy would continue to result in delays 

in accessing the park, affecting visitor experience. Also, in the future, increasing growth in the 

region could result in increased visitation at the park, potentially increasing the number of times 

when visitors experience delays in accessing the park. While technological improvements at the 

entrance station are anticipated to reduce the number of times visitors experience delays in 

entering the park, the park would consider new measures, if delays to enter the park do increase 

due to increased demand in the future. Therefore, under Alternative A there would be no 

impairment of transportation systems within or near the park. 
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GREAT FALLS PARK, VIRGINIA y FINAL GMP/EIS 4.8

4.1.5 Impacts on Site Utilities 

Under Alternative A, there could be negligible impacts on water supply and sanitary sewer 

systems due to the proposed improvements to existing restroom facilities, which may result in a 

slight increase in the use of potable water and create more wastewater. No other impacts are 

anticipated on site utilities. 

Cumulative Impacts

 

Under Alternative A, no cumulative impacts are anticipated on site utilities. 

Conclusion

The measures proposed under Alternative A would not result in the impairment of the park’s 

utility system. 

4.1.6 Sustainability and Long-Term Management 

 

Short-Term Use of the Environment versus Long-Term Productivity 

Under Alternative A, the impacts of back-ups along Old Dominion Drive, use of a flood-prone 

space in the visitor center by park staff, and inadequate space for park staff are not likely to be 

sustainable as the Washington DC metropolitan region continues to spread and demand for 

recreation in the park grows. These conditions could adversely affect long-term protection and 

enjoyment of park resources. 

Irreversible and Irretrievable Commitments of Resources 

Under Alternative A, there would be a potential for irreversible or irretrievable damage to 

cultural resources, especially to the Matildaville ruins, due to the park’s inability to commit 

enough resources to mitigate natural and visitor-related impacts on these resources. 

Unavoidable Adverse Impacts

Deterioration and eventual loss of some of the park’s cultural resources may be considered an 

unavoidable adverse impact. Even if visitation does not increase considerably, the heavy use of 

the trails within vicinity of the visitor center, and the movement of visitors away from formal 

trails, would continue to impact sensitive cultural and natural resources. 
ENVIRONMENTAL CONSEQUENCES 

4.9 NATIONAL PARK SERVICE 

4.2 ALTERNATIVE B – PREFERRED ALTERNATIVE 

 

This section of the document identifies potential impacts on resources that could result under 

Alternative B (Preferred Alternative). 

 

4.2.1 Impacts on Land Use and Socio-Economic Conditions 

Land Use, Property Boundaries, and Land Protection 

Under the Preferred Alternative, there would be temporary, minor impacts on the surrounding 

uses from construction-related activities at the park. The demolition of the maintenance facility, 

construction of the replacement operations (including maintenance) facility at the same 

location, and improvements at the visitor center, would result in temporary, constructionrelated traffic. No long-term impacts are anticipated on surrounding uses. 

There are no boundary changes proposed under the Preferred Alternative. In the future, the 

park may undertake establishing a revised boundary based on the criteria identified in Chapter 2 

of this document. At that time, in accordance with NEPA, the park may undertake additional 

environmental analysis to determine impacts resulting from the boundary change. 

Establishing boundaries does not necessarily constitute a proposal to purchase the land within 

those boundaries. A variety of land protection methods are available within the authorized 

boundaries of the park units. In addition to fee simple acquisition, scenic, conservation, and 

access easements might be acquired, or local zoning and cooperative planning and management 

could be employed. 

Visitation and Visitor Activities

 

Under the Preferred Alternative, it is unlikely that visitation would significantly increase or 

decrease in the short-term. Similar to Alternative A, in the long-term, the projected growth in 

the region would likely result in an increase in visitation at the park. Under existing conditions, 

visitors experience delays entering the park an average of 10 to 15 times per year. Technological 

improvements at the entrance station are anticipated to alleviate some of this delay. Also, the 

proposed electronic message boards and the radio signal would help to reduce some of the 

delays by conveying the traffic conditions to visitors, giving them an opportunity to visit other 

parks in the region. If the visitation increases considerably in the future, the number of days 

when delays are experienced along Old Dominion Drive and potentially Georgetown Pike could 

increase, resulting in an adverse impact. 

Similar to Alternative A, connecting the park to regional trails could mitigate some of this 

potential pressure, since visitors could access the park via non-motorized modes of 

transportation. However, depending on the increase in visitation demand, NPS could explore 

alternative means of providing access to the park in the future, including connecting Great Falls 

Park to a potential regional shuttle system. 

Also, similar to Alternative A, connecting the park to regional trails would provide visitors 

additional recreational opportunities and would result in a positive impact on visitor 

experience. 
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GREAT FALLS PARK, VIRGINIA y FINAL GMP/EIS 4.10

The demolition of the maintenance facility, removal of the USPP trailer, construction of the 

replacement operations facility, and improvements at the visitor center would result in a 

temporary, moderate adverse impact on visitor experience of the park’s visitor facilities. 

However, over the long-term, visitors are anticipated to benefit from enhanced interpretive and 

educational opportunities that would be offered at the visitor center to provide a better 

understanding of the park’s resources. 

Overall, there would be a positive impact on visitor experience due to an increase in interpretive 

and educational programs. As identified in Chapter 3, approximately 73 percent of the visitors 

surveyed (in 1996) indicated that viewing the Great Falls was their predominant activity at the 

park; 41 percent of visitors surveyed indicated that viewing wildlife was their predominant 

activity; while 31 percent indicated visiting the Potomac Canal as their predominant activity. The 

visitors participating in these and other activities would benefit from an enhancement in exhibits 

and interpretive material, as well as access to cultural resources at the park, as proposed in the 

following actions: 

y Expand interpretive programs including promoting safety and providing guidance on 

how to recreate in a manner that minimizes impacts on park’s resources: This would 

include converting the space currently occupied by park staff in the visitor center (VC) 

to spaces for visitors. These measures would expand opportunities for resource 

interpretation at the park, while minimizing adverse impacts from visitor use on sensitive 

resources. 

 

y Preserve unexposed cultural resources by leaving them buried below the surface except 

in a few locations where uncovering them would significantly benefit interpretation at 

the park and not have an adverse impact on the resource: Where cultural resources are 

uncovered, visitors would benefit from added resources that would become available for 

them to understand the significance of the park’s cultural resources. 

y Stabilize and protect Matildaville: A plan to stabilize and protect Matildaville, that 

would include increasing interpretation of the resource, would also benefit visitor 

experience. 

The Preferred Alternative would include several actions that would result in potential adverse 

impacts on visitation and visitor experience, as identified below: 

• Issue an ‘access pass’, on a trial basis, to visitors seeking to engage in climbing, fishing, or 

scientific research in the area between the southern end of Overlook #3 and the Sand 

Box climbing area: Since the park would provide this pass on a seasonal basis, in 

unlimited quantities, and free-of-charge, and since this would be a temporary condition 

until a Climbing Management Plan (CMP) is prepared, no adverse impacts are 

anticipated for visitors engaging in these activities. However, this measure would result 

in a temporary adverse impact on casual visitors since they would not be able to access 

this area. 

• Prepare a Climbing Management Plan that could potentially close specific areas on a 

temporary, periodic or permanent basis: The park is currently engaged in a study to 

assess any impacts climbing activities may have on cliff habitat and rare plant species. If 
ENVIRONMENTAL CONSEQUENCES 

4.11 NATIONAL PARK SERVICE 

adverse impacts are determined from climbing activities in the vicinity of sensitive 

resources, the park would develop measures to reduce such impacts. These measures 

could include limited use of anchors, access pass for certain areas, temporary or periodic 

closures, or under extreme conditions, permanent closures. These measures could 

modify the existing pattern of use for climbers and if a route is closed permanently, result 

in an adverse impact. The park will work with the public during the preparation of the 

CMP to address these concerns further and to develop measures that result in minimal 

impacts on the climbing community. 

• Prepare a Trails Management Plan that could require the realignment or closure of horse 

access to portions of Matildaville Trail and Mine Run Trail to minimize potential 

damage to resources: During the preparation of the Trails Management Plan (TMP), the 

park would undertake a study to evaluate impacts of trail activities on sensitive natural 

and cultural resources. If adverse impacts are determined from horseback riding in the 

vicinity of sensitive resources such as the Mine Run or Matildaville, the park would 

develop measures to reduce such impacts. These measures could include fencing off 

areas, realigning trail segments or, under extreme conditions, closing routes. These 

measures could modify the existing pattern of use for horseback riders and if trails are 

closed, result in an adverse impact on these users. However, if the trails are realigned, 

there would be minimal impact on these users. The park will work with the public 

during the preparation of the TMP to address these concerns further and to develop 

measures that result in minimal impacts on the horseback riding community. 

Community Facilities - Police, Fire, and Rescue Services

Under Alternative B, message boards would be provided along Georgetown Pike, and a radio 

announcement would inform visitors of the traffic and parking conditions within the park. 

These measures are anticipated to reduce vehicular traffic back-ups along Old Dominion Drive, 

which would help to improve police, fire, and rescue service access to the park during 

emergencies. Also, similar to Alternative A, technological improvements at the entrance station 

are anticipated to improve emergency access at the entrance station. 

Under Alternative B, the holding tank off Jackson Lane would be expanded. This would 

provide additional water for use during fire emergencies and would result in a positive impact. 

Neighboring Population and Socio-Economic Conditions

 

The socio-economic characteristics of the area surrounding the park primarily includes 

established residential communities, with institutions interspersed within. Similar to Alternative 

A, changes in the management and operations of the park in accordance with Alternative B are 

not anticipated to result in a change in population characteristics in the study area, or result in 

the addition or elimination of large number of jobs. Therefore, impacts anticipated on the 

neighboring population and socio-economic conditions would be negligible under the 

Alternative B. 
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GREAT FALLS PARK, VIRGINIA y FINAL GMP/EIS 4.12

Cumulative Impacts

 

Under the Preferred Alternative, there may be temporary cumulative impacts when activities 

within the park are examined in conjunction with anticipated activities outside the park. If the 

duration of demolition/construction at the park occurs simultaneously with construction of the 

proposed Cross County Trail (CCT), Potomac Heritage National Scenic Trail (PHNST), or the 

Georgetown Pike Trail (GPT), there would be temporary and minor adverse impacts on 

surrounding land uses due to these construction activities. 

Conclusion

Under the Preferred Alternative, short-term adverse impacts on visitor experience would 

include potential delays in entering the park, renovation activities at the visitor facility, and 

demolition and construction activities at the maintenance facility site. Also, depending on the 

strategies developed as part of the TMP, potential realigning or closing portions of Matildaville 

and Mine Run Trails could affect horseback riders. Similarly, depending on the strategies 

developed as part of the CMP, potential closure of climbing sites on a temporary, periodic or 

permanent basis could affect climbers. In the long-term, connections to regional trails would 

expand recreational opportunities for visitors at the park, resulting in a beneficial impact. Also, 

in the future, increasing growth in the region could result in increasing visitor demand to access 

the park. Since there is no proposal to increase parking within the park, added demand could 

increase the number of times when visitors experience delays in accessing the park. If that 

happens, the park would consider new measures to reduce the periods when visitors experience 

delays in accessing the park. Overall, while visitor experience may be modified for some users, 

the Preferred Alternative is not anticipated to result in the impairment of park resources or 

visitor experience of the park. 

 

4.2.2 Impacts on Cultural Resources 

 

Archaeological and Historic Resources

 

The following actions are aimed to support these policies. Their potential impacts on cultural 

resources within the park would be as follows: 

y Prepare a Trail Management Plan, eliminate most undesignated trails, restrict new 

undesignated trails from developing, and recommend best practices such as potentially 

fencing areas where trails are located adjacent to sensitive areas: Under these measures, 

visitor access near sensitive resources would be managed to a greater degree compared 

to current conditions. During the preparation of the TMP, the park would examine 

undesignated trails on a case-by-case basis and eliminate most that adversely affect 

sensitive cultural resources. The park would also examine each designated trail on a 

case-by-case basis and adopt measures that could include potential realignment or, 

under extreme circumstances, potential closures on a temporary, periodic or permanent 

basis of trail segments that result in adversely affecting sensitive cultural resources. Since 

these measures would be aimed at reducing the potential damage to historic and 

archaeological resources, including the Patowmack Canal, a designated National 

Historic Landmark, they would result in a positive impact. 
ENVIRONMENTAL CONSEQUENCES 

4.13 NATIONAL PARK SERVICE 

y Rehabilitate the visitor center to improve exhibits and establish an educational 

component that would focus on resource interpretation: Additional interpretive exhibits 

and educational programs are anticipated to strengthen a visitor’s understanding of the 

park’s exceptional resources, as well as the benefits of protecting and preserving these 

resources. This measure is anticipated to result in a positive impact on the park’s 

archaeological and historical resources. 

y Preserve unexposed cultural resources by leaving them buried below the surface except 

in a few locations where uncovering them would significantly benefit interpretation 

without adversely impacting the resource: This measure would allow for the continued 

preservation of most buried ruins. While uncovering selective sites for professional 

historical and archaeological research would be a positive impact as it would help to 

increase knowledge and expand interpretation, the sites would be exposed to the natural 

environment and could be adversely impacted in the long-term. Adequate measures 

should be adopted to ensure the continued preservation of the selective sites that would 

be uncovered. 

y Develop a plan to stabilize and protect Matildaville: Under this alternative, the park 

would increase active management of Matildaville. This resource contributes to the 

Patowmack Canal’s cultural landscape and improving interpretation of this linkage, as 

well as adopting measures to prevent further damage of this resource, would result in a 

positive impact. 

 

y Develop an Integrated Resource Management Plan (IRMP) to protect sensitive cultural 

resources from potential vegetation damage and adopt best management practices 

(BMP) to protect cultural resources that are either listed, or eligible for listing, on the 

National Register: As described under Alternative A, these measures are anticipated to 

result in a beneficial impact since the IRMP and BMPs would seek to minimize potential 

damage from trees and other vegetation on cultural resources, including the Patowmack 

Canal and Matildaville. 

 

Viewsheds

 

Under the Preferred Alternative, the preparation of a Viewshed Management Plan would result 

in a beneficial impact since it would identify policies for preservation, maintenance, and 

restoration of important scenic views from vantage points within the park and adjacent areas. 

Also, the following changes would influence the existing viewsheds within and outside the park: 

y View of the maintenance facility: The existing maintenance facility would be replaced by 

a replacement operations facility. This would be located immediately north of the 

entrance station and would be visible to visitors entering/exiting the park. The design of 

this replacement facility would influence a visitor’s entrance experience at the park. 

Therefore, to result in a positive visual impact, the design of the facility should be 

sensitive to its highly visible location. 

y Views from C & O Canal NHP: The proposed operations facility, to be located at the 

site of the existing maintenance building, is unlikely to be visible from the C&O Canal 

NHP, due to the existing vegetative buffer along the river’s edge. However, if a tall 
CHAPTER 4 

GREAT FALLS PARK, VIRGINIA y FINAL GMP/EIS 4.14

structure is constructed as part of the proposed facility, it has the potential to be 

observed from across the river. The park should ensure that appropriate visual analysis 

is conducted during the design of this facility to confirm that no adverse impacts result to 

views from C&O Canal NHP. 

Cumulative Impacts

 

Under the Preferred Alternative, no cumulative impacts are anticipated on cultural resources, 

when activities within the park are examined in conjunction with anticipated activities outside 

the park. 

Conclusion

Under the Preferred Alternative, protection of cultural resources at the park would be enhanced 

due to the proposed development of a TMP that would include elimination of most 

undesignated trails, preparation of a IRMP, establishment of an education component that 

would focus on resource interpretation, and developing a plan to stabilize and protect 

Matildaville. Leaving most ruins buried would also benefit those resources; however, if some 

ruins are uncovered for interpretation purposes, the park would adopt adequate measures to 

ensure that these are not impaired. Therefore, the Preferred Alternative would not result in the 

impairment of cultural resources. 

4.2.3 Impacts on Natural Resources 

Their potential impacts on natural resources within the park would be as described below: 

Geophysical Resources

Under the Preferred Alternative, no impacts are anticipated on geological resources, 

topography, or soils. 

Water Resources

 

Watersheds and Resource Protection Areas 

Under the Preferred Alternative, the park would provide technical assistance to neighbors on 

water resource management techniques. In addition, the park would demonstrate the use of 

these techniques when improving the visitor center or during the construction of the 

replacement operations facility. These measures would raise awareness, as well as identify 

measures to reduce the impacts of stormwater runoff on the area’s watershed, and therefore are 

anticipated to result in a positive impact on water resources. 

Surface and Groundwater 

Under the Preferred Alternative, preparation of the TMP that would include eliminating 

existing undesignated trails and prohibiting new undesignated trails could have an indirect 

positive impact, as visitors would be guided away from sensitive areas along the edges of existing 

streams, water bodies and groundwater recharge areas or seeps. In addition, best practices such 
ENVIRONMENTAL CONSEQUENCES 

4.15 NATIONAL PARK SERVICE 

as fencing around sensitive areas, realigning, or closure under extreme circumstance of horse 

access to portions of trails (such as Mine Run Trail in the vicinity of Clay Pond) would reduce 

potential erosion-related impacts, as well as potential impacts related to horse manure, resulting 

in a positive impact. The park would continue to monitor trail use and make necessary repairs 

and trail improvements to minimize other erosion-related impacts prior to realigning or closing 

segments of trails. 

Wetlands and Waters of the United States 

Under the Preferred Alternative, no direct impacts are anticipated on existing wetlands within 

the park. However, eliminating existing undesignated trails and prohibiting new undesignated 

trails could have an indirect positive impact as visitors would be guided away from sensitive 

areas such as those adjacent to the Potomac River. Also, an effort to educate visitors through 

increased interpretive programs regarding benefits of preserving wetlands could result in an 

indirect positive impact. During the preparation of the TMP, in case the park develops a new 

trail alignment or a new trail, the park would conduct a wetland delineation to ensure that the 

new segment does not impact such areas. 

Floodplains 

Under the Preferred Alternative, the park would relocate staff offices from the lower level of the 

visitor center to a replacement facility to be constructed at the site of the maintenance facility. 

The visitor center is located within Potomac River’s 100-year floodplain. Under the Preferred 

Alternative, the lower portion of the visitor center would be used to support the proposed 

educational function. Since this area would still be prone to flooding, the park should use this 

space for non-habitable uses with removable furniture and equipment to prevent flood-related 

damage. 

 

The existing maintenance facility borders the western edge of the Potomac River’s 100-year 

floodplain, with a portion of the facility possibly within the floodplain. The area within the 100-

year floodplain is also designated as a resource protection area, in Virginia, under the 

Chesapeake Bay Preservation Act (CBPA). Under the Preferred Alternative, the park would 

construct a replacement facility at this location. In accordance with DO #77-2 (Floodplain 

Management), the park would undertake a detailed study of this site to identify the extent of the 

floodplain. If possible, the replacement facility would be located outside the floodplain. 

However, if the floodplain covers most of this site such that portions of the replacement facility 

would be within the 100-year floodplain, the replacement facility would be designed such that 

the amount of impervious surface within the floodplain would be kept the same as current 

conditions. This would be in accordance with the CBPA. Further, the facility would be 

sustainably designed such that habitable space would be located above the flood zone, and 

mitigation measures would be identified to minimize potential loss of property during a flood 

event. Consistent with DO #77-2, a Statement of Findings would be prepared as part of further 

analysis if portions of this facility are located within the floodplain. 

 
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GREAT FALLS PARK, VIRGINIA y FINAL GMP/EIS 4.16

Water Quality 

Under the Preferred Alternative, no water quality impacts are anticipated within or adjacent to 

the park. Difficult Run would continue to remain impaired since the park’s contribution to this 

watershed is extremely small. However, the park would work with its neighbors and other 

regional agencies to adopt measures that would help to improve this water body. 

Biological Resources

Vegetation 

Under the Preferred Alternative, there are several proposed changes that would impact existing 

vegetation within the park. These include the following: 

y Explore the development of USPP stables off Jackson Lane: The area off Jackson Lane 

consists of approximately seven acres, the majority of which is wooded. Developing 

stables and a paddock area for horses may require clearing some of the existing 

vegetation in this area and could result in a minor adverse impact. Prior to pursuing this 

option in the future, the park would undertake further studies of the site including 

additional environmental documentation and a survey for potential archaeological 

resources. Also, prior to pursuing this option, the park would engage in a discussion with 

neighbors to determine any potential concerns. Therefore, no impacts are anticipated at 

this time. 

y Eliminate most existing undesignated trails and prohibit new undesignated trails: These 

changes may result in a minor positive impact as visitors would be guided away from 

sensitive vegetation along highly managed trails, and overlook areas adjacent to the River 

Trail. 

y Develop an Integrated Resource Management Plan (IRMP) to protect sensitive cultural 

resources from potential vegetation damage and adopt BMPs to protect cultural 

resources, especially those that are listed on the National Register: An IRMP and BMPs 

are typically developed to reduce or eliminate potential environmental impacts. During 

the preparation of the IRMP and BMPs, the park would seek to protect sensitive cultural 

resources without adversely impacting biological resources. Therefore, this measure is 

not anticipated to result in an adverse impact. 

Wildlife Habitat 

Under the Preferred Alternative, no impacts are anticipated on wildlife habitat within and 

adjacent to the park. 

Rare, Threatened, and Endangered Species 

Under the Preferred Alternative, several changes are proposed that have the potential to impact 

rare, threatened, and endangered species within the park. The proposed changes include the 

following: 
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4.17 NATIONAL PARK SERVICE 

y Eliminate most undesignated trails, and prohibit additional undesignated trails: These 

efforts would reduce potential damage to sensitive areas as visitor movement would 

predominantly be restricted to designated trails. This would reduce potential damage to 

rare, threatened, and endangered species within the park, resulting in a positive impact.

• Designate a trail to access the area between the southern end of Overlook #3 and the 

Sand Box climbing area, and issue an ‘access pass’, on a trial basis, to visitors seeking to 

engage in climbing, fishing, or scientific research in this area: This measure would limit 

casual visitors from accessing an area that includes the globally rare Central 

Appalachian/ Piedmont riverside prairie and several State listed rare plant species. By 

requiring visitors with access passes to stay on a designated trail, the park would 

minimize the potential of impacts on this sensitive resource. During the preparation of 

the CMP, the park would examine whether to continue the access pass policy. 

y Prepare a Climbing Management Plan that could potentially close specific areas on a 

temporary, periodic or permanent basis: The park is currently engaged in a study to 

assess any impacts climbing activities may have on cliff habitat and rare plant species. If 

adverse impacts are determined from climbing activities in the vicinity of sensitive 

resources, the park would develop measures to reduce such impacts which would result 

in a beneficial impact. These measures could include limited use of anchors, access pass 

for certain areas, temporary or periodic closures, or under extreme conditions, 

permanent closures. The park will work with the public during the preparation of the 

CMP to address these concerns further and to develop measures that result in minimal 

impacts on the climbing community. 

Air Quality

Under the Preferred Alternative, there would be minor, short-term construction-related, 

adverse impacts to air quality as a result of demolition of the maintenance facility, and 

construction of the replacement operations facility. Emissions produced during construction 

would vary daily depending on the type of activity. However, it is the total annual emissions by 

which the conformity exemption is calculated, and these are not anticipated to exceed the 

minimum thresholds. During demolition and construction activities, the park would take 

reasonable precautions to minimize release of polluting elements. Such precautions could include 

covering open equipment that convey construction materials, or watering construction areas to 

minimize the release of dust particles. 

Potential reduction in vehicular traffic back-ups along Old Dominion Drive due to improved 

signage would reduce localized vehicular emissions, resulting in a positive impact. 

Noise Levels

Under the Preferred Alternative, there would be minor, construction-related, adverse impacts 

on park visitors during demolition of the maintenance facility, construction of the replacement 

operations facility, and renovation of the visitor center. Visitors would be subject to 

construction noise as they drive or walk by the location of the maintenance facility or when they 

visit the visitor center. These impacts would be temporary, lasting through the duration of 

construction. 
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GREAT FALLS PARK, VIRGINIA y FINAL GMP/EIS 4.18

The movement of heavy trucks hauling demolition waste, excavated soil, and construction 

materials would generate noise that could result in a temporary adverse impact on residences 

along Old Dominion Drive and Georgetown Pike. 

There would be no anticipated increase in operational noise impacts. 

Hazardous Materials

Under the Preferred Alternative, building materials removed during the demolition of the 

maintenance facility and renovations at the visitor center could potentially contain asbestos, 

lead, or other hazardous materials. Also, any excavation at the maintenance facility site could 

potentially disturb soils that may contain contaminants. During excavation and demolition 

activities, soils that are suspected of contamination and wastes that are generated will be tested 

and disposed according to all applicable federal, state, and local laws and regulations. These 

include, but are not limited to, the Virginia Waste Management Act, the Virginia Hazardous 

Waste Management Regulations, and the Virginia Solid Waste Management Regulations. 

Cumulative Impacts

 

Under the Preferred Alternative, several potential cumulative impacts could affect natural 

resources. These include the following: 

y There would be temporary construction-related impacts on local air quality and noise, 

depending upon the duration of demolition/construction activities within the park, and 

the proposed CCT, PHNST, and GPT. 

y Similar to Alternative A, the anticipated growth in the region’s population could result in 

increasing visitation to the park. This could result in a considerable increase in vehicles 

waiting to access the park, resulting in a minor adverse impact on localized air quality. 

Also, the existing natural habitats within the park could be further burdened if the area 

around the park is developed in response to some of this anticipated regional growth. 

Conclusion

Under the Preferred Alternative, protection of natural resources at the park would be enhanced 

due to the proposed development of a CMP, a TMP that would include elimination of most 

undesignated trails, and establishment of an education component that would focus on resource 

interpretation. The anticipated growth in the area’s population could result in increasing 

visitation and potentially burdening the existing natural habitats within the park. If demand for 

accessing the park increases substantially, the park would explore additional measures to 

minimize potential impacts on the existing natural resources. Potentially locating portions of a 

replacement facility in the 100-year flood zone could result in a negligible impact on the 

floodplain. Consistent with DO #77-2, a Statement of Findings would be prepared as part of 

further analysis if portions of the proposed replacement facility are located within the 

floodplain. Therefore, the Preferred Alternative would not result in the impairment of natural 

resources. 
ENVIRONMENTAL CONSEQUENCES 

4.19 NATIONAL PARK SERVICE 

4.2.4 Impacts on Transportation Systems 

The potential impacts under Alternative B on transportation systems within and adjacent to the 

park would be as follows: 

• Introduce technology that expedites payment and other operational functions at the 

entrance station: Similar to Alternative A, potential technological improvements at the 

entrance station, such as where pass holders would swipe their cards to gain access, 

would increase the processing rate, and reduce the waiting time at the gate for all visitors. 

Provided the parking lots are not full, queues that currently form during peak arrival 

periods would be reduced or potentially eliminated. This would result in a positive 

impact on visitor access to the park. 

• During severe crowding, initiate a one vehicle out, one vehicle in policy: Similar to 

Alternative A, during severe crowding, visitors waiting in line would be informed to 

expect delays. Vehicle crowding would continue to result in a minor adverse impact on 

visitor access to the park. 

• Place dynamic message boards (signs) along transportation routes leading to the park 

(Georgetown Pike and Old Dominion Drive) and add a radio announcement to indicate 

when the parking lots are full: Message boards on Georgetown Pike and a radio 

announcement would alert visitors that the parking lots are full at Great Falls Park. By 

having dynamically updated information available on signs on Georgetown Pike, and on 

a particular radio channel, visitors would be provided with an opportunity to make a 

decision before turning onto Old Dominion Drive – whether to wait in line for parking, 

or seek to visit other parks in the area. These measures are anticipated to result in a 

positive impact on visitor access to the park. 

Cumulative Impacts

 

Under the Preferred Alternative, there could be potential temporary adverse cumulative impacts 

from construction-related traffic on area roadways if demolition/construction activities in the 

park (demolition of maintenance facility, construction of the replacement operations facility, 

etc.) occur during the same period as construction of the proposed PHNST, CCT or GPT 

outside the park. 

Also, similar to Alternative A, over the long-term, the projected growth in the region could 

increase visitation at the park. This could result in additional days when delays are experienced 

along Old Dominion Drive and potentially Georgetown Pike, resulting in an adverse impact on 

the area’s transportation systems. 

Conclusion

Under the Preferred Alternative, the one vehicle out, one vehicle in policy would continue to 

result in delays in accessing the park. Also, in the future, increasing growth in the region could 

result in an increase to visitation at the park, potentially increasing the number of times when 

visitors experience delays in accessing the park. If that happens, the park would consider new 

measures to reduce such delays. The proposed message boards and radio announcement would 
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GREAT FALLS PARK, VIRGINIA y FINAL GMP/EIS 4.20

inform visitors about parking and traffic conditions at the park and are anticipated to benefit 

visitor accessibility. Overall, under the Preferred Alternative, there would be no impairment of 

the park’s resources under transportation systems. 

4.2.5 Impacts on Site Utilities 

Under the Preferred Alternative, the demolition and construction of a replacement facility at the 

maintenance facility site would result in construction-related impacts on utilities. Also, while no 

impacts are anticipated on water and sanitary sewer systems due to the anticipated expansion of 

restroom facilities, additional water and wastewater system models and a utility capacity study 

should be performed prior to undertaking these improvements. The expansion of the water 

tank along Jackson Lane would result in providing additional potable water to the park, 

resulting in a positive impact. 

If public water is extended to the park in the future, the park would coordinate the route and 

access to the existing water main (located at the intersection of Georgetown Pike and State 

Route 683) with the Fairfax County Water Authority. 

Cumulative Impacts

 

Under the Preferred Alternative, no cumulative utility impacts are anticipated. 

Conclusion

The measures proposed under the Preferred Alternative would not result in the impairment of 

the park’s utility system. 

4.2.6 Sustainability and Long-Term Management 

 

Short-Term Use of the Environment versus Long-Term Productivity 

Alternative B proposes several actions that would have short-term adverse effects, but would 

result in improving the long-term productivity of the park, including: 

y Improvements at the visitor center would temporarily result in reducing exhibit space 

and impacting interpretive programs for visitors. However, over the long-term, 

improvements to exhibits, as well as visitor programs at the visitor center, would benefit 

the interpretation and long-term productivity of the park’s cultural and natural 

resources. 

y Demolition of the maintenance facility and construction of the replacement operations 

facility would impact management operations at the park over the short-term. However, 

over the long-term, the management of the park would improve due to improved spaces 

for the various operations-related uses. 

y Removal of existing undesignated trails would result in changing the current pattern of 

use. Over the long-term, this would help to preserve sensitive natural and cultural 

resources. 
ENVIRONMENTAL CONSEQUENCES 

4.21 NATIONAL PARK SERVICE 

Irreversible and Irretrievable Commitments of Resources 

Construction activities under Alternative B would require the use of building materials that are 

often drawn from natural resources. The materials used at the park would be sought from the 

existing building construction industry, similar to other construction projects in the region. 

While using natural and fabricated building materials in the park would be irreversible, none of 

these materials would be considered limited or scarce resources whose use at Great Falls Park 

would threaten the continued availability or existence of that resource. 

Unavoidable Adverse Impacts 

Deterioration and eventual loss of some of the park’s cultural resources may be considered an 

unavoidable adverse impact. The heavy use of the trails within vicinity of the visitor center 

would continue to impact sensitive cultural and natural resources.