HomeMy WebLinkAboutSUB201000156 Review Comments 2011-03-046,01A
COUNTY OF ALBEMARLE
Department of Community Development
401 McIntire Road
Charlottesville, Virginia 22902
4 Mar 2011
Charlotte Hisey John Sinclair Robert B. Goss
1249 Maple View Drive 445 Maple View Court The Inn at Monticello
1188 Scottsville Road
(emailed to stay @innatmonticello.com)
Re: Willow Lake stream buffer
You have requested to be advised of my position on the building setbacks that will apply to a
proposed development next to the pond referred to as Willow Lake. From your letter, I
understand that a 20' building setback is being used by the developer of lots adjacent to the pond.
I also understand that you believe a 100' setback should apply based on section 17 -317 of the
Water Protection Ordinance, and the assertion that this lake is a contiguous wetland to Cow
Branch.
Staff at the county make a clear distinction between the terms "building setback ", and "stream
buffer ", and consider them two separate and distinct terms. A building setback is defined in the
Zoning Ordinance based on the zoning of subject and abutting parcels. A stream buffer is
defined in the Water Protection Ordinance and based on the nature and location of streams and
bodies of water. In this letter I am clarify the stream buffer, as given in section 17 -317.
The enabling legislation for the County's Water Protection Ordinance sections on stream buffers
is found in the Chesapeake Bay Preservation Act. In administering the ordinance, I rely on the
Chesapeake Bay guidance documents found on the Virginia Department of Conservation and
Recreation web site. These documents speak to the placement of RPA (Resource Protection
Area) buffers on contiguous non -tidal wetlands.
Willow Lake is a unique circumstance not directly addressed in the guidance literature. It is a
man made impoundment separated from a perennial stream by a berm. It is not known what
existed in the area of the impoundment previously, or if the berm separating it from Cow Branch
is natural or was built with the dam.
The county's initial assessment, which is seen on the county's graphical information system,
viewable on -line, shows no intermittent or perennial stream coming into or leaving the pond.
This is shown below;
Albemarle County
Community Development
County Engineer letter
Page 2
This information comes from county aerial photography and from USGS mapping. The USGS
maps for this area show a similar and less detailed picture;
Given this information, it appeared that this pond was created on a low point in the topography
with a drainage area adequate to keep it full, but not on a natural stream, and not dependent on
Albemarle County
Community Development
County Engineer letter
Page 3
the perennial flow in Cow Branch to keep it full or to keep any of the wetland vegetation which
may surround it saturated. This means it was not considered contiguous in a hydrologic sense.
Based on this information, and the language in 17 -317A, which you quoted in your letter, the
Water Protection Ordinance stream buffer was placed only on Cow Branch, the perennial stream.
As with all county mapping, this is an initial assessment. If field conditions are found to differ
from the maps, this assessment can change. This possibility was allowed for in 2008 when the
Board of Supervisors adopted an amendment to the Water Protection Ordinance which changed
the definition of a perennial stream for purposes of establishing stream buffers. Section 17-
104(32) states;
"(32) Perennial stream. The term "perennial stream" means any stream that is depicted as a
continuous blue line on the most recent United States Geological Survey 7.5 minute topographic
quadrangle maps (scale 1:24,000) or which is determined by the program authority to be perennial
following a site - specific evaluation using the guidance entitled "Determinations of Water Bodies with
Perennial Flow," dated September 2003, issued by the Chesapeake Bay Local Assistance Department. This
definition shall not apply to streams within a development area or area of infill and redevelopment that
have been piped or converted legally and intentionally into stormwater conveyance channels such that the
stream does not resemble or maintain the characteristics of a natural stream channel, as determined by the
program authority."
If the channel entering the pond was evaluated in detail and found to be perennial according to
the above procedure, the stream buffer would include it and the pond through which it flows.
The document referenced in the ordinance makes use of a protocol developed by Fairfax County,
which when used by a competent professional, would be very adequate.
Please contact me if you have questions.
Sincerely,
Glenn Brooks, P.E.
County Engineer
Copy: Bill Fritz, Chief of Current Development