Planning Department
Plans and Procedures
Appendix
B. Critical Lots
- Designation
of Critical Lots. Lots are designated critical during
the concept plan review process based on soil conditions, degree
of slope, flooding, or other lot features, and to address concerns
related
to the feasibility of construction as described in Sections 3-3.2
and 3-3.3.
- Zoning
Code Requirements. All critical lots shall meet the applicable
requirements of the Zoning Code, including but not limited to Sections
17.28.030, 17.28.040, and 17.28.050.
- Critical
Lot Plan Required. Prior to application for a building
permit on a lot designated as "critical," a
plan shall be submitted to the Executive Director for approval.
The plan shall provide
a survey of existing conditions, details of the proposed development,
and address any concerns in relation to the feasibility of construction
on the lot as follows:
- Critical lot plans shall be drawn at a scale of 1"=20'-0".
- The critical lot plan shall show existing conditions, to a
point 10 feet outside the lot boundaries, including:
- contour lines at 2-foot intervals.
- the location and elevation of the curb or edge of pavement
fronting the lot and the elevation
of the driveway at the house.
- lot dimensions, easements, setbacks, etc. which are shown
on the recorded plat or a note designating
setbacks to be
determined by the
zoning and/or any easements if not shown on the plat.
- existing tree masses and locations of existing trees of
8" caliper
or greater, including any to be removed.
- ground elevation at the base of the trees.
- notations of significant features such as streams, springs,
rock outcrops, and sinkholes;
and, if applicable,
the floodplain
as shown
on the final plat.
- The critical lot plan shall also include the exact proposed building
footprint and garage and
first
floor elevations;
location of other
proposed lot improvements; proposed contour lines
(including driveways) at 2-foot intervals; top
and bottom elevations
of retaining walls
and materials of wall construction; specified
and illustrated methods of
stabilization of slopes greater than 33% grade
including silt fencing and other temporary measures; limits
of grading; existing
trees
to be preserved and methods of preservation;
and methods of managing stormwater
runoff by keeping the water on the lot.
- For lots in a floodplain, the plan shall show the minimum finished
floor
elevations.
- It is emphasized that a typical house design may not be suitable
for a critical lot and a
house designed
specifically
for the
lot may be necessary.
- The Executive Director may request additional technical evaluation
and analysis of a proposed
critical lot
by a professional engineer
specializing in geotechnical, soils, hydrology,
and/or structures.
- Critical
Lot Plan Review. Three copies of the critical lot plan shall be
submitted to the Executive Director to initiate a staff review.
The critical lot plan shall include the name and phone number of
the
person responsible for the preparation of the plan and the number
for a contact person. Within 14 days of the submittal date, the
staff member
responsible for the review shall notify the applicant of the approval
or disapproval of the plan or the plan changes necessary to gain approval.
- Basis
for Critical Lot Plan Approval. Critical lot plan approval shall
be based on the care taken to minimize the lot area subject to
grading, the cut/fill required to prepare the lot for construction,
and the effectiveness of the plan to preserve the natural features
of the lot and stormwater flow management details.
- General
Guides for the Critical Lot Plan. The following are typical
review items, but not all inclusive:
- Driveways crossing sidewalks in compliance with the Public
Works Department accessibility standards.
- The diversion of runoff away from foundations.
- Grading near lot boundaries that does not undercut trees on
adjacent lots or direct
stormwater flow to adjacent lots and
structures.
- Grading at the minimum necessary to allow for building construction.
- Avoidance of excessive foundation and retaining wall heights.
- Details of any retaining walls.
- Details of tree preservation.
- All information described on the Critical Lot Checklist available
from the Executive Director.
- Issuance
of Building Permits. No building permit shall be issued at any
time prior to approval of the critical lot plan.