2b Wetland Accessory Structure CITYOF
690 Ci0, Ce,ter Drive
PO Box I47
Chanhassen, Minnesota 55317
Phone
952.937.1900
General Fax
952.937.5739
Engineering Department Fax
952.937.9152
Building Department Fax
952.934.2524
Web Site
wwu: cl. cha,ha,e,, mn. us
MEMORANDUM
TO:
Planning Commission
FROM: Planning Department
DATE: April 17, 2001
Zoning Ordinance Amendments
BACKGROUND
Originally, the City required a 75-foot setback from the edge of a wetland. Since
manicured lawns were being maintained up to the wetland's edge on most
properties, the ordinance was amended in 1992 to require a vegetated buffer and
allowed a reduced setback. Buffers allow a reduced setback while maintaining
water quality benefits.
SUMMARY
Wetland Accessory Structure Setback
The wetland setback ordinance currently does not address setback requirements
for accessory structures. The existing wetland ordinance states that the wetland
setback requirements pertain to "structures," however, the setback table specifies
only "principle structure setback," thus our dilemma. The proposed revision
specifies that the setback would be the same for principle and accessory
structures.
The issue of limiting the amount of impervious surface for accessory structures in
wetland setbacks was discussed at previous meetings. Staff believes that
specifying a maximum percentage of impervious surface or a maximum square
footage of structures would be difficult to administer. For instance, specifying a
maximum square footage of an accessory structure may allow some structures
like a small shed, but excludes others that may be more appropriate, like a play
set, which could be as large as 22 feet by 22 feet. Setting a standard for
impervious surface would be troublesome since the determining the amount of
hard surface for some structures may be difficult. For example, a deck is not
typically considered hard surface because water can permeate through the cracks
of the decking, so it would be difficult to determine the amount of impervious
surface.
The City of Chanhassen. A
Planning Commission
April 17, 2001
Page 2
wetlands. In a Single Family Residential District, accessory structures may be up to 1,000
square feet in area. In Rural Residential and Agricultural Districts, there are no size limitations
except for the overall lot coverage limitation. Permitting accessory structures closer than the
principle structure could be highly detrimental to the protection of wetlands.
Therefore, we recommend that the setback specified in the existing ordinance be maintained for
both principal and accessory structures.
The provision has been amended as follows:
Section 20-406. Wetland buffer strips and setbacks.
Wetland Type
Principal and
Accessory
Structure Setbacks
Buffer Strip'
Pristine Natural Ag/Urban Utilized
100' 40' measured 40' measured 0'
from the from the
outside edge outside edge
of the buffer of the buffer
strip, strip
20-100' 10-30' 0-20' 0'
Buffer Strip
Minimum Average
Width
% of Native
Vegetation in Buffer
Strip
50' 20' 1 O' O'
Entire ' Entire Optional Optional
l
This change will clarify the ordinance for all structures, as it currently only includes primary
structures.
Planning Commission
April 17, 2001
Page 3
RECOMMENDATION
"Staff recommends the Planning Commission recommend approval .to the City Council the
following code amendment adding accessory structure to the setback requirements:
ARTICLE VI. Wetland Protection
Section 20-406 Wetland buffer strips and setback (a)
Wetland Type
Principal and
Accessory
Structure Setbacks
Buffer Strip
Pristine
100'
20-100'
Natural Ag/Urban Utilized
40' measured 40' measured 0'
from the from the
outside edge outside edge
of the buffer of the buffer
strip strip
10-30' 0-20'
1
Buffer Strip
Minimum Average
Width
% of Native
Vegetation in Buffer
Strip
50' · 20' 10' O'
Entire Entire Optional Optional
g:~plan\bgXzoa 4-17-01 wetland setback.doc
/
CITY OF CHANHASSEN
CARVER AND HENNEP1N COUNTIES, MINNESOTA
ORDINANCE NO.
AN ORDINANCE AMENDING CHAPTER 20 OF THE
CHANHASSEN CITY CODE, THE ZONING ORDINANCE
The City Council of the City of Chanhassen ordains:
Section 1. Section 20-406 (a), Wetland buffer strips and setbacks, is hereby
amending the table as follows:
Wetland Type Pristine
Principal and Accessory 100'
Structure Setbacks from the from the
outside edge outside edge
of the buffer of the buffer
strip strip
Buffer Strip 20-100' 10-30' 0-20' 0'
Natural Ag/Urban Utilized
40' measured 40' measured 0'
Buffer Strip Minimum
Average Width
50' 20' 10' 0'
% of Native Vegetation Entire
in Buffer Strip
Entire Optional Optional
Section 2. This ordinance shall be effective immediately upon its passage and publication.
PASSED AND ADOPTED by the Chanhassen City Council this
2001.
of
ATTEST:
Scott A. Botcher, City Manager
(Published in the Chanhassen Villager on
Linda C. Jansen, Mayor