REV2 REFERENCE BLD2023-0699+CHANGE REQUEST+6.11.2024_12.32.53_AM+4313222VdidALrENGINEERING
CONSTRUCTION CHANGE REQUEST
TO: CITY OF EDMONDS & OCW&SD
FROM: REBECCA SCOTT VADER, PE
PROJECT & SUBJECT: 2420 EDMONDS TAP HOUSE BLD2023-0699
DATE: 2024-06.10
Enclosed: I For Your:
Herewith Approval
Information X Review x
Your use
Under Separate Cover
Construction
Record — BLD2023-0699
Via:
Email x_
Print
Quantity Type and Description
1
Copy of Change order request to OVWSD and Edmonds approved Water-1 drawing markups, in red and
clouded on WP-3 and WP-4 of Approved Drawings by others.
1
Cut Sheet for Enclosure Aqua Shield BFP6-N
1
Olympic View Water & Sewer District Standard Detail W-13
1
Ford fitting specification
1
Email selection
Remarks:
The transmitted Engineering documents have been prepared in conformance with sound
engineering principles and standards, with the best available site and technical information,
and with the standard of care typical in this time and locale. The Engineering documents
contained herein has been prepared by the undersigned Professional Engineer Licensed in the
State of Washington.
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www.vaderengineering.com ♦ 6817 27t" ST W, #65353 Tacoma, WA 98466 + 253.363.2065
Project
6/11/2024
Response to Correction Notice
Fire Line DCDA and Hotbox
1. The DCDA was installed per the Water Change Request made to OVW&SD and cc to
Edmonds on or about 4-18-24. It was our understanding that OVW&SD has jurisdictional
authority over the Water Supply to the point of the DCDA, and we will take corrective action to
supply all the materials to Edmonds as well, through the My Building Permit Portal.
This change was requested because of constructability issues with the approved vault. There
are 2 constructability issues that are resolved with the requested change: Horizontal Conflicts
with existing gas and power lines, and Vertical Conflicts that would either produce a less safe
situation for departing vehicles if the vault is too high (approved) or fall risk in parking lot is
vault is lowered.
The Horizontal conflicts existed because the size of the exterior of the vault is too close to the
other utilities for constructability, especially given the bending alignments depicted that
increasingly narrow the gap and the accuracy of standard locate techniques. The Contractor
evaluated installation to the original plan, and determined it likely to cause damage beyond the
approved limits.
The Vertical conflicts show on the profile view in the approved drawings. The top of the vault
was +- 4' above the sidewalk grade at the point behind the walk where a departing vehicle
would stop. This is the most important grade differential for safety but was obscured by the
profile view. With the typical AASHTO sight distance using a drivers height of 3.5 ft, the — 4 ft
high approved vault obstructs the view of oncoming traffic for a vehicle departing to the left.
The Change request improves this condition by rotating the obstruction, choosing a narrower
enclosure, and moving the obstruction of the DCDA Enclosure the maximum practicable away
from the ROW toward the building, so it is behind the driver's position, thus clearing the sight
triangle and improving vehicle safety compared to the approved plan.
The vault as approved, at > 30" above standable surrounding grade, also did not meet the fall
protection needs of the workers who will have to enter the vault for DCDA testing and
maintenance. The contractor noticed this because they also service installed DCDA assemblies
Attempts to correct the vertical conflicts by either lowering the vault likewise caused > 30"
drops from the parking lot side, so there was no compliant path for future service workers to
access the vault, lift the hatches, and enter/exit. This is rectified by the rotated, above -ground
enclosure which has lift off side openings that allow access from the parking lot side at
approximately the same grade, so the change is safer for people compared to the approved
vault.
Please note that both the approved plan and the change request incorporate this required
utility appurtenance at > 36" above grade, simply at different elevations and the change is
7az&!&ENGINEERING
Project
6/11/2024
further from the ROW. We will be able to respond directly to specific corrections from Planning
once they are received.
Water Service Line
1. Construction is a sequential process, with partially completed work sometimes in view while
other work is ready for inspection. For instance, this can occur when constructing joint trenches
with different depth of utilities, as is the case for this project.
On the date inspected, the inspection was for the Fire Service Line, so the Fire line, as the
lowest utility, was still exposed for that inspection. The domestic water is to be installed above
the fire line, so could not yet be bedded or brought to clearance elevation until the Fire line was
approved to be backfilled.
As a response to the notice of correction, after Fire Line backfill is allowed, the domestic service
line will be brought to the elevation to achieve the 1' vertical separation.
2. As a response to the notice of correction, after Fire Line backfill is allowed, the granular sand
for the domestic service line bedding will be placed.
3. To clear up concerns about the suitability of Ford fittings, they are a well -established fitting
type commonly used not only by the local water district having jurisdiction, but many other
jurisdictions both in and beyond the state of Washington. OVW&SD, which routinely uses this
fitting type, has graciously provided the attached manufacturer's specifications. And, as I am
told, provided them as a direct email as well within a day of seeing the correction notice.
Distribution: File 2420
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