Summary Statement:

This metadata summary applies exclusively to the data as it appears in this Loudoun County intranet/internet mapping application. To see the fully FGDC compliant version of this metadata click here.

Abstract:

MDOD Metadata/Map Disclaimer
The Circuit Court of Loudoun County issued an opinion dated March 30, 2004 ruling that the Mountainside Development Overlay District (MDOD) is void. The 1993 Mountainside Development Overlay District (MDOD) regulations in effect prior to adoption of the revised 2003 MDOD on January 6, 2003, will apply in the administration of zoning regulations. The March 30, 2004 decision may be the subject of an appeal.

The Mountainside Development Overlay District is a zoning overlay district administered by the Department of Building and Development. Mountainside classifications are based upon the following criteria: critical elevation, debris flow (slippage) potential, groundwater recharge, soils, slope, and forest values. Critical elevation areas are determined from the County's digital topography, soil and slope values are based upon data from the County's soil layer, and forested areas are based upon the digital forest data. This original MDOD replaces the voided layer implemented in 2003 (see disclaimer above).

As a result of the adoption of the new Loudoun County Zoning Ordinance on Dec 13, 2023, two new protection features were added to the Overlay District, Stream & Ridge Protection Features. Covered activies are not allowed within either protection area, with the stream protection areas being a 300ft buffer.

Purpose:

The Mountainside Development Overlay District is a zoning overlay district (see Section 4-1600 of the 1993 Loudoun County Zoning Ordinance) and regulates development on the mountainsides of the County. Mountainside data should be used for general planning purposes only and is not intended for use in delineating specific use or suitability of soils for a particular site. Areas prone to debris flow (slippage) may not be accurately delineated. The Department of Building and Development is responsible for final clearance and interpretation on zoning/building permits and land development applications for the Mountainside Development Overlay District.

Supplemental Information:

Mountainside classifications are based upon the Mountainside Development Overlay District Soils Worksheet available from the Office of Mapping and Geographic Information or the County's soil scientist in the Department of Building and Development. Mountainside sensitivity classifications are based upon the mside-val item, which is a sum of the mountainside soil value, mountainside critical elevation value and mountainside forest value. A mside-val score of 9 is Somewhat Sensitive, scores of 10-13 are Sensitive, and scores of 14 or greater are Highly Sensitive. Critical elevations are different for Catoctin (550’) than for Blue Ridge and Short Hill (both 700’). The digital mountainside data was compiled in 1999 and has not since been updated. The mountainside data does not reflect changes made to forests, soils, slopes, and topography since 1999. The current mountainside criteria as outlined on the worksheet came into effect in 1991. Data are stored in the corporate ArcSDE Geodatabase as a feature class. The coordinate system is Virginia State Plane (North), Zone 4501, datum NAD83 HARN.

Maintenance and Update Frequency:

Typically can only change when land development proposals are presented in concert with more current or more accurate base layers; site specific surveys, new topo, new forestry, etc., Mountainside boundaries may be modified as part of the Comprehensive Plan rewrite.

Completeness Report:

Features may have been eliminated or generalized due to scale and intended use. To assist Loudoun County, Virginia in the maintenance of the data, please provide any information concerning discovered errors, omissions, or other discrepancies found in the data.

Mountainside Development Overlay District Worksheet items to calculate Mountainside Sensitivity

Mountainside Critical Elevation Values

0:        Below Critical Elevation (550' for Catoctin Ridge, 700' for Short Hill and Blue Ridge)
3:        Sensitive

Mountainside Forest Values

0:        Not Forested
2:        Forested

Mountainside Soil Values

Range of values from 2-18; Per select unit types and their sum of designated values for mountainside soil location, groundwater recharge, slippage, and steep slopes.

Mountainside Sensitivity Values

9:              Somewhat Sensitive
10 - 13:        Sensitive
14 and greater: Highly Sensitive

Data Owner:

Department of Building and Development