4752338 Zoning Commission Notice of Proposed Rulemaking: Case No. 13-06 (Text Amendments Relating to Retaining Walls

ZONING COMMISSION FOR THE DISTRICT OF COLUMBIA

 

NOTICE OF PROPOSED RULEMAKING

Z.C. Case No. 13-06

(Text Amendment – 11 DCMR)

(Text Amendments Relating to Retaining Walls)

 

The Zoning Commission for the District of Columbia, pursuant to its authority under § 1 of the Zoning Act of 1938, approved June 20, 1938 (52 Stat. 797, as amended; D.C. Official Code § 6-641.01 (2012 Repl.)), hereby gives notice of its intent to amend § 199, Chapter 1 (Zoning Regulations), and adding a new § 413 to Chapter 4 (Residence District: Height, Area, and Density Regulations), of Title 11 (Zoning) of the District of Columbia Municipal Regulations (DCMR).

 

The proposed text amendments would clarify zoning regulations as they pertain to retaining walls. The text amendments define the term “retaining wall,” clarify the process for measuring retaining walls, and provide regulations for Residence Districts to determine the maximum height for retaining walls, based on: whether the wall is located between a property line and building line, whether the wall is located on a block with street frontage, and whether the wall abuts an improved alley. The text amendments permit the Board of Zoning Adjustment to grant special exception relief from these regulations for retaining walls not meeting the requirements of new § 413.

 

Final rulemaking action shall be taken in not less than thirty (30) days from the date of publication of this notice in the D.C. Register.

 

The following amendments to the Zoning Regulations are proposed:

 

Chapter 1, THE ZONING REGULATIONS, is amended by adding the following definition to § 199 in alphabetical order:

 

Retaining Wall - a vertical, self-supporting structure constructed of concrete, durable wood, masonry or other material, designed to resist the lateral displacement of soil or other materials.  The term shall include concrete walls, crib and bin walls, reinforced or mechanically stabilized earth systems, anchored walls, soil nail walls, multi-tiered systems, boulder walls or other retaining structures.

 

Chapter 4, RESIDENCE DISTRICT: HEIGHT, AREA, AND DENSITY REGULATIONS, is amended by adding a new § 413, Retaining Walls, to read as follows:

 

413                  RETAINING WALLS

 

413.1               In R-1, R-2, R-3, and R-4 Districts a retaining wall may be erected in accordance with the requirements of this section.

 

413.2                              The height of a retaining wall shall be determined as follows:

 

(a)                The height of a retaining wall is the vertical distance measured from the lowest level of the ground at the base of the wall to the top of the wall;

 

(b)               When the height of a retaining wall varies, the height shall be measured at the highest point of the wall, from the lowest level of the ground at the base of the wall at that point; and

 

(c)                Berms or other similar forms of intermittent terrain elevation shall not be included in measuring retaining wall height.

 

413.3                              Subject to the height limitations of §§ 413.4 through 413.7, the maximum height of a retaining wall shall be six feet (6 ft.). 

 

413.4                              A retaining wall shall not exceed four feet (4 ft.) in height in the following locations, unless a lower height is required by §§ 413.5 and 413.6:

 

(a)                Along a street frontage or property line;

 

(b)               Within any required side yard;

 

(c)                In the R-1 Districts, within twenty-five feet (25 ft.) of the rear property line, as measured from the rear property line inward; and

 

(d)               In the R-2, R-3, and R-4 Districts, within twenty feet (20 ft.) of the rear property line, as measured from the rear property line inward.

 

413.5                              A retaining wall located along a street frontage on a block with adjacent existing retaining walls shall not be greater in height than the tallest adjacent existing retaining walls up to the maximum height of four feet (4 ft.).

 

413.6                              A retaining wall located on any area between a property line and a building line shall not exceed a maximum height of forty-two inches (42 in.).

 

413.7                              A retaining wall abutting an improved alley in the R-3 or R-4 Districts shall not exceed a maximum height of twelve feet (12 ft.).

 

413.8                              Retaining walls may be tiered or terraced provided that the slope does not exceed a 2:1 horizontal to vertical ratio.  The area between walls shall be pervious and may not be paved or otherwise covered with impervious materials.

 

413.9                              Retaining walls not meeting the requirements of this section, may be approved by the Board of Zoning Adjustment as a special exception pursuant to § 3104.1.  In addition to meeting the general conditions for being granted a special exception as set forth in that subsection, the applicant must demonstrate that conditions relating to the building, terrain, or surrounding area would to make full compliance unduly restrictive, prohibitively costly, or unreasonable. 

 

All persons desiring to comment on the subject matter of this proposed rulemaking action should file comments in writing no later than thirty (30) days after the date of publication of this notice in the D.C. Register.  Comments should be filed with Sharon Schellin, Secretary to the Zoning Commission, Office of Zoning, 441 4^th Street, N.W., Suite 200-S, Washington, D.C. 20001. Ms. Schellin may also be contacted by telephone at [phone] or by email: at [e-mail].  Copies of this proposed rulemaking action may be obtained at cost by writing to the above address.