ARTICLE II. GENERAL REGULATIONS

(1) Any residential, commercial, industrial use, or combination thereof, where the anticipated average weekday twenty-four (24) hour traffic generation, using the Trip Generation Manual (Institute of Transportation Engineers, Fifth Edition or as it may from time to time be amended) equals or exceeds one thousand (1,000) trip ends or where the traffic volume during a peak hour equals or exceeds one hundred (100) trip ends unless the zoning administrator shall determine, in writing, that such analysis is unnecessary due to the existence of previous studies and analyses which adequately cover the extent of the proposed development and its traffic impact.

(2) Any development or subdivision of a portion of property where the potential average weekday twenty-four (24) hour traffic generation, using the Trip Generation Manual (Institute of Transportation Engineers, Fifth Edition or as it may from time to time be amended) for the developable portion of the entire property based on permitted uses under existing zoning equals or exceeds one thousand (1000) trip ends or where the traffic volume during a peak hour equals or exceeds one hundred (100) trip ends, regardless whether the remainder of the property is currently proposed for development unless the zoning administrator shall determine, in writing, that such analysis is unnecessary due to the existence of previous studies and analyses which adequately cover the extent of the proposed development and its traffic impact.

(3) Any request for amendment of the zoning map or for a special use permit other than those requests initiated by the commission or board, where the anticipated average weekday twenty-four (24) hour traffic generation, using the Trip Generation Manual (Institute of Transportation Engineers, Fifth Edition or as it may from time to time be amended) equals or exceeds one thousand (1000) trip ends or where the traffic volume during a peak hour equals or exceeds one hundred (100) trip ends unless the zoning administrator shall determine, in writing, that such analysis is unnecessary due to the existence of previous studies and analyses which adequately cover the extent of the proposed development and its traffic impact.

(4) Any non-residential development which proposes to access a street which is residential in character and classified as a minor collector or lower order street.

(5) Any other development proposal which, as determined by the zoning administrator, has a significant potential to cause or aggravate traffic safety or congestion problems and, as such, would benefit from a professional review of proposed access and circulation designs.

(1) For any development described in subsection (a) above, a traffic impact analysis, prepared by a transportation engineer or planner, shall be submitted for review and consideration by the county and the Virginia Department of Transportation. A minimum of five (5) copies of such traffic impact analysis shall be submitted to the county at the same time as the initial application for development or zoning approval. Subdivision plats, site plans, rezoning applications, use permit applications, and other development proposals for which a traffic impact analysis is required shall not be deemed to be received until the traffic impact analysis is submitted.

(2) The submitted traffic impact analysis shall, unless otherwise approved by the zoning administrator in writing, contain the following information and analysis:

a. Existing conditions summary-including twenty--four (24) hour volumes, peak periods and peak volumes on adjacent roadways, peak periods and peak volumes of the generator, and peak hour factor(s); roadway geometrics; grades; lateral clearance; heavy vehicle, pedestrian, bicycle, and recreational vehicle percentages; existing lane configurations; traffic control devices and timing plans if signals are present and, if appropriate, level of service analysis.

b. Future conditions summary--including the horizon (analysis) year(s) and the criteria used in its selection, committed future roadway improvements, traffic growth factors combined with forecasts for adjacent sites to determine future background traffic (both twenty-four (24) hour and peak period), and, if appropriate, level of service analysis, compared with existing conditions.

c. Trip generation and design hour volumes--including traffic forecast for site development to include twenty-four (24) hour and peak hour volumes both for the traffic generator itself and on adjacent roadways. Trip Generation Manual (Institute of Transportation Engineers, Fifth Edition, or as it may from time to time be amended) rates or equations shall be used unless verifiable local data is available. Any assumptions or adjustments shall be fully documented and, where appropriate, justified with source references provided.

d. Trip distribution and traffic assignment--including a directional distribution of site traffic to its area of influence based on primary market, analogy, origin-destination, gravity model, or other similar methods. Each step in the process shall be fully and carefully documented.

e. Design year total volumes--developed for both twenty-four (24) hour and for the peak periods of the generator and on adjacent roadways.

f. Capacity analysis--including intersection and lane capacity based on the 1994 Highway Capacity Manual as it may from time to time be amended and revised. Where intersections (both signalized and unsignalized) are spaced in such proximity or the volumes are such that the intersection does not operate independently, appropriate progression and queuing analyses performed using a recognized methodology or analysis or simulation package must accompany the capacity analyses.  Capacity analyses shall be prepared for each potential access design scenario. Any assumptions and adjustments to the default values in the 1994 Highway Capacity Manual shall be fully documented and justified. These include, but are not limited to, peak hour factor, average running speeds, and cycle lengths, especially very short or long cycles. All worksheets shall be submitted.

g. Traffic accidents and safety analysis. The distribution and frequency of traffic accidents shall be analyzed and a determination made as to whether any safety deficiencies exist or will be caused or exacerbated. This shall specifically include a safety analysis of all proposed street extensions.

h. Traffic improvements. The recommended roadway and traffic network improvements based on the design hour in the design year shall be shown on a scaled plan sheet with appropriate narrative. Such improvements shall be designed to yield a minimum level of service of "C" as defined by the 1994 Highway Capacity Manual as it may from time to time be amended, supplemented, or revised. Where the existing conditions provide a current level of service of less than "C," the improvements shall be designed to at least maintain the current volume to capacity ratio as determined by the methods contained in the 1994 Highway Capacity Manual without further degradation through the design year plus two (2) years. A detailed construction cost estimate of the required improvements shall be provided.

i. Internal site improvements. Including the number and width of driveway lanes, the appropriate throat lengths (both unobstructed and with cross traffic permitted) for ingress and egress points, stacking and queuing lanes, pedestrian accommodations, bicycle facilities, and any other facilities or accommodations and any other factor which could impact traffic operations along the adjacent roadways or overall traffic safety, both internal and external. The internal circulation system shall be designed to preclude stacking or queuing in the travel lanes of adjacent roadways during the peak hours of the traffic generator.

j. Conclusions. Including all conclusions of the analyst applicable to the site, particularly with respect to the appropriate timing and phasing of improvements. Timing and phasing must be clearly tied to identifiable stages of development or specific time frames. Conclusions about the relative safety of the post-development situation shall also be included.

k. Summary of findings and recommendations. An executive summary containing key findings and recommended actions.

(3) All intersections, commercial entrances, median breaks, pavement markings, driveways, or other roadway features potentially affecting traffic flow located within five hundred feet (500') [150m] of the proposed development as well as all intersections and driveways internal to the development shall be considered and either shown or clearly noted on a scaled plan submitted with the traffic impact analysis.