HomeMy WebLinkAboutPN_Project_Narrative_180315_v1.pdfPreliminary Project Narrative
For
Haevin Ridge Short Plat
Haevin Ridge Short Plat is a proposed 6-lot single-family development located in the South
Benson Planning Area of Renton on the west side of 116th Avenue SE just south of Benson Hill
Elementary School. The site consists of a single legal parcel with a total site area of
approximately 57,847 SF (1.33 acres):
Parcel # 3223059075
Address: 18809 116th Avenue SE., Renton 98058
There are no existing dwelling structures located on the site. The existing residence originally
located on the property burned down in 2016. Currently the site is vacant except for the cell
towers at the west end of the property and a crosswalk operation building located along the north
property line. Existing access is a driveway off 116th Ave. SE. The site is within the city limits
and zoned R-8. Parcels within the vicinity of the site on the west side of 116th are zoned
Residential Medium Density. Parcels on the east side of 116th are zoned Residential Low density.
There are two outside uses that currently exist on the property – a small building housing a
Comcast Internet Hub located mid-site along the north property line (noted on the plans as
Telecom I) and a cell tower in the northwest corner (noted on the plans as Telecom II). Both
operate on the property under separate easement agreements and are currently accessed from
116th via common access easement located on the Benson Hill Elementary school property. It is
our intent to convert both easements into permanent tracts within the plat. Access to these tracts
will remain on the school property.
A storm water tract is proposed for locating a vault to provide detention and water quality
treatment for the projects storm water runoff. It will be located between the Telecom I and II
tracts on the north side of the site. Access to this facility will be from the proposed access road
on the south side of the plat between Lots 3 and 4. An easement along the south side of proposed
Lot 6 will be required to connect the storm drainage outfall from the proposed vault to the
existing storm drainage system located in 116th Avenue SE. Due to shallowness of the existing
storm drainage system in 116th Avenue SE, it will be necessary to extend new storm drainage
pipe for approximately 190 feet north within the 116th Avenue right-of-way before connection to
this shallow system can be made.
The site slopes gently from west to east toward 116th Avenue SE with an average slope of around
6% to 7%. A portion of the site slopes toward the west with an average slope of around 2% to
2.5%. Ages Engineering, LLC performed a site evaluation of site soils in August 2017. In a
report dated August 16, 2017, he describes the on-site soils as consisting of 1.0 to 1.5 feet of
disturbed native soils or topsoil overlying silty sand and gravel consistent with glacial till. Three
test pits dug on the site, all finding similar soil conditions.
Preliminary earthwork quantities include approximately 1,500 cubic yards of cut (including the
vault) and 800 cubic yards of fill to achieve grades shown on the current preliminary grading
plan. These numbers do not factor in actual house foundations, which will likely lower the
current estimated fill amounts if crawl spaces are utilized.
There are currently 51 existing trees located on the site that are of sufficient size to meet the
“significant tree” definition. Of these, 14 have been classified as “dangerous” by a certified
arborist, 6 are located in areas proposed to be dedicated as rights-of-way, and 2 are located
within a proposed private access tract, leaving 29 on-site significant trees. At this time, site plan
density, buildable areas, grading and utilities allow for the retention of at least 4 of those trees
which equates to approximately 14% significant tree retention. Per code, the project is required
to retain 30% (9 trees) or plant replacement trees. Using the Tree Retention Worksheet and based
on retaining 4 significant trees, this project will need to provide an additional 60 caliper inches of
replacement trees. Assuming that replacement trees will be 2-inch caliper, this equates to
approximately 30 replacement trees.
116th Avenue SE is classified as a minor arterial. Existing improvements along that site frontage
include one travel lane each way and paved shoulders and fog lines. Proposed improvements
along this frontage include a 5.5-foot right-of-way dedication along our frontage for a total half
right-of-way width of 35.5 feet. This is consistent with the City of Renton Transportation
Department’s corridor plan to provide a 71-foot right-of-way for this section of 116th Avenue SE.
Roadway improvements from right-of-way centerline will include 22 feet of pavement, vertical
curb & gutter, 8-foot planter strip and 5-foot concrete sidewalk. As mentioned above, an
extension of new storm drainage pipe will be required for approximately 190 feet in 116th
Avenue to connect to the existing shallow storm drainage system.
An internal access street is proposed for this development. The internal street is proposed to be a
half-street consisting of a 35-foot dedicated right-of-way, 20 feet of paving, vertical curb &
gutter, 8-foot planter strip and 5-foot concrete sidewalk. Lots 1-5 and the storm water tract will
access via this street. Lot 6 will have its own driveway directly onto 116th Avenue SE.
A small job shack can be anticipated on-site during construction. It is not currently known if a
model home will be utilized as a sales tool for work on the other lots.
General Site Statistics:
Zoning designation:
R-8
Existing Use:
Residential single-family
Proposed use:
Residential single-family
Proposed Lots Info:
No. of Lots: 6
Size: Ranging from 5,000 SF to 5,850 SF.
Dedication to the City:
5.5-foot right-of-way dedication along 116th Ave SE and 35-foot half right-of-way along portion
of southern property line (9,412 SF).
Proposed Density:
5.39 DU/acre (see density worksheet)
Access:
Access to Lots 1-5 and the proposed storm water tract shall be via a new public road off 116th set
in new 35-foot half right-of-way. Access to lot 6 shall be via driveway directly to 116th Avenue
SE.
Off-Site Improvements:
Addition of curbs, sidewalk and planter strips along frontage to 116th Avenue SE with minimal
pavement replacement. Pavement cut / patch will be required for mainline utility connections for
water, sewer and storm. Storm drainage pipe extension of approximately 190 feet.
Utility Purveyors:
Sanitary Sewer – Soos Creek
Domestic Water – Soos Creek
Anticipated Permits required:
Preliminary Short Plat, Utilities / Clear and Grade, Right-of-Way, Building.
Special features:
No sensitive areas or special features on or near the property.
Estimated Construction Cost:
$1,200,000 (Home Construction, Public Road Improvements, Utility Infrastructure)
Estimated project Value:
$3,600,000 ($600,000 / home)