City of Rockville

M E M O R A N D U M

July 15, 1999

TO: Planning Commission

FROM: Jim Wasilak, Planner III

SUBJECT: Comprehensive Planned Development Concept Plan CPD99-0004, Fallsgrove

For the first worksession on the Fallsgrove Concept Plan, the discussion will focus on the Forest Stand Delineation and Natural Resources Inventory, and how the proposal has addressed the draft Environmental Guidelines. It is hoped that this will aid the Commission in its deliberations on the application in September.

Environmental Background

The purpose of the Natural Resources Inventory (NRI) is to delineate the environmental features of the site in advance or early in the review process to allow for the protection of these features and result in an environmentally-friendly site design. A primary component of the NRI is the Forest Stand Delineation (FSD), which is required by the City's Forest and Tree Preservation Ordinance. The NRI also includes, among others, delineation of streams and floodplains and their associated buffers, wetlands, stream quality, topography, threatened and endangered species, existing wildlife and cultural resources.

Fallsgrove Associates have prepared an NRI for the property in accordance with the guidelines. The NRI identified significant forest stands along the eastern side of the property, stream valleys and the corner of West Montgomery Avenue and Shady Grove Road. Note that given the R-S zoning of the property, 20 percent of the land area must be in forest cover, either through retention or reforestation. The three streams on the property, tributaries of Watts Branch, require a minimum 125 foot stream buffer. The required buffers for wetlands are also shown.

Issues

The applicant has agreed to meet the intent of the Environmental Guidelines and designed the project accordingly. At the urging of the City, the upland forest near the intersection of West Montgomery Avenue and West Gude Drive in addition to those forest stands located within the stream buffer areas to be preserved. Any utility or trail construction in these areas will minimize impacts on the treed areas. The Final Forest Conservation Plan will identify areas of conservation and reforestation for the property.

By adhering to the stream buffers, the applicant has been able to design the project around the resulting open space areas. These will be a defining feature of the project. Other environmentally sensitive aspects of the site design include minimal stream crossings, retention of existing topography and preservation of significant views along the tree-lined driveway. The applicant has also agreed to perform a one-year baseline environmental monitoring programming, including stream and well monitoring, that will evaluate the existing conditions, the impact of construction and the effectiveness of stormwater management Best Management Practices (BMPs). A Phase II environmental assessment will identify the presence of herbicides, pesticides and other toxic substances in the soil and groundwater.

There are some unknowns that could impact the environmental features of the site, including the ultimate alignment of Gude Drive and the ultimate location of stormwater management facilities. In addition, the applicant has requested that an area of stream valley buffer be subject to buffer averaging, in that a comparable area of land outside the stream buffer would be preserved in exchange for allowing encroachment into a buffer area. This area has been requested in the northern portion of the site between Research Boulevard and West Montgomery Avenue in order to allow a more developable land bay. In addition, an area of prior converted cropland near the intersection of Darnestown Road and Shady Grove Road is awaiting final determination as such, which could result in a mitigation requirement.

/rjw

Attachment

1. NRI summary page