HomeMy WebLinkAboutPN_Project_Narrative_LOMRF_15022_135thAveSE_260413_v2Project Narrative – Shoreline Exemption / LOMR-F Compliance
Property Address:15022 135th Ave SE, Renton, WA 98058
Parcel Number:2223059057
Zoning:R-4 Residential
Owner/Applicant:Ferose Babu
Estimated Project Cost / Fair Market Value:approximately $240 for the physical fill work.
Project Overview
This application requests a Shoreline Exemption for an after-the-fact minor fill activity within
the Cedar River shoreline jurisdiction and mapped 100-year floodplain. During summer 2025, an
estimated 2.41 cubic yards of clean fill material, consisting primarily of topsoil and gravel, was placed
adjacent to the existing single-family residence and detached garage in thin layers to restore grades
near the foundations and improve drainage away from the structures. No new construction occurred.
The site is outside the regulatory floodway and within the Shoreline Residential Environment.
Purpose and Need
The site lies within the FEMA Special Flood Hazard Area (SFHA) in both Zone AE (riverine flooding
from the Cedar River) and Zone AO (1-foot shallow flooding / ponding). Harmsen Engineering and
WEST Consultants reviewed the effective FEMA Flood Insurance Study (FIS) model and concluded
that the controlling Zone AE Base Flood Elevation (BFE) is approximately 77.8 feet NAVD88 at
the residence and 77.9 feet NAVD88 at the garage. This narrative uses 77.9 feet as the conservative
controlling elevation.
As documented in the previously submitted residence Elevation Certificate, the exterior HVAC
unit serving the residence on the west / southwest side is at elevation 78.9 feet NAVD88, which is
approximately 1.1 feet above the residence AE BFE of 77.8 feet NAVD88.
The minor fill was placed to raise and restore the Lowest Adjacent Grades (LAG) of the house and
garage above the controlling AE BFE as part of a Letter of Map Revision Based on Fill (LOMR-F)
request to FEMA. The intent is to document that both the residence and detached garage are
reasonably safe from flooding and to support removal of both structures from the mapped SFHA,
including both mapped AE and AO designations affecting the property.
Existing and Proposed Use
The site is developed with an existing single-family residence, detached garage, driveway, deck,
septic improvements, lawn, and associated landscaping. The proposed use will remain the same. No
new structures, lot subdivision, increased lot coverage, parking expansion, or change in access is
proposed.
Existing Site Conditions
•Lot Area:11,100 sq ft (0.25 acre)
•Frontage:approximately 80 ft along Cedar River (medium bank)
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•Topography and critical areas:Gently sloping lawn area with portions of the site,
particularly the river bank area, mapped as regulated slopes under the City’s critical areas
code. The minor fill occurred within the existing lawn near the house and garage and did not
disturb regulated slope areas or required buffers.
•Surface Cover:Existing lawn and landscaping only; no trees removed.
•Drainage / soil conditions:The work occurred in an already-developed residential yard
with lawn and near-surface topsoil in the immediate work areas. Surface flow is directed
toward the street and around the existing structures, as shown on the stamped site plan.
Shoreline Setting
The adjacent shoreline water body is the Cedar River. Along the subject property, the shoreline is a
riverine floodplain edge with a medium bank. The work area is landward of the OHWM and outside
the floodway. The minor fill did not include in-water work, bank armoring, new bulkheading, or
alteration of the riverbank.
Completed Work
As shown on the stamped site plan P_Floodplain_Site_Plan_15022_135thAveSE_260410_v1.pdf,
the estimated fill areas total 2.41 cubic yards, consisting of fill area (1) at approximately 87 square
feet / 0.84 cubic yards and fill area (2) at approximately 84 square feet / 1.57 cubic yards. The fill
was placed around limited portions of the residence and garage foundations in thin layers to restore
eroded grades and improve drainage away from the structures. No excavation below historic grades
at the foundations, structural work, or bank alteration occurred.
Compensatory Storage
To comply with RMC 4-3-050 E 3(g), equal or greater compensatory storage is provided on-site
at approximately the same elevation range as the minor fill. As shown on the stamped site plan
P_Floodplain_Site_Plan_15022_135thAveSE_260410_v1.pdf, the estimated cut areas total 3.72
cubic yards, which exceeds the estimated 2.41 cubic yards of fill. Compensatory storage consists of:
•Cut area (3), approximately 600 square feet / 1.78 cubic yards, within the lawn area identified
on the updated site plan; and
•Cut area (4), approximately 104 square feet / 1.94 cubic yards, in the additional regraded
area shown on the updated site plan.
These cut areas provide more storage volume than the estimated 2.41 cubic yards of fill and maintain
natural drainage patterns. The updated site plan also shows the AO / AE delineation, drainage
paths, contours, fill and cut areas, compensatory storage areas, property corner elevations, and
other surveyed vertical information requested in the City’s February 27, 2026 review memo. No
underground storm drainage pipes are proposed or identified within the scope of this minor fill
activity.
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Environmental Considerations
No impact to riparian vegetation, fish, or wildlife habitat is anticipated from this minor after-the-fact
fill. No in-water work or disturbance of the riverbank is proposed. No trees were removed. No
off-site improvements or land dedication are proposed.
Supporting Materials
•P_Floodplain_Site_Plan_15022_135thAveSE_260410_v1.pdf; and
•RS_BFE_Determination_15022_135thAveSE_260202_v1.pdf.
Summary
This request qualifies for a Shoreline Exemption under RMC 4-9-190 C.1 for a minor alteration
associated with an existing single-family residence. The work has no adverse environmental impact,
satisfies compensatory-storage requirements, and supports FEMA floodplain-compliance efforts.
The City of Renton reviews the minor fill for conformance with applicable City code; FEMA, not
the City, will make the final LOMR-F determination.
Prepared by:
Ferose Babu, Property Owner
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