HomeMy WebLinkAboutCD 2023-0006; CARLSBAD DESALINATION PLANT INTAKE AND DISCHARGE MODIFICATION: CONSTRUCTION METHOD MODIFICATION; Admin Decision LetterMay 18, 2023
Gregory Amparano
Poseidon Resources (Channelside) LP
5780 Fleet St., Ste 140
Carlsbad, CA 92008
{'Cityof
Carlsbad
8FILE COPY
SUBJECT: CD 2023-0006 -CARLSBAD DESALINATION PLANT INTAKE AND DISCHARGE
MODIFICATION: CONSTRUCTION METHOD MODIFICATION (DEV2023-0074)
The City Planner has completed a review of your application for a Consistency Determination (4590
Carlsbad Blvd., APNs 210-010-45 and 210-010-49). CD 2023-0006 modifies part of the intake and discharge
infrastructure of the Carlsbad Desalination Plant by changing the construction method of how the Dual
Flow Screen (DFS) structure and adjacent deck are anchored into and below the seabed of Agua Hedionda
Lagoon.
Background. The DFS structure and adjacent deck are parts of the desalination plant's partially submerged
intake system in the lagoon. These and other features of the plant's intake and discharge system are under
construction following their approval by the Planning Commission on Oct. 5, 2022 (CUP 2022-0010 and
SUP 2022-0006) and the city planner on Nov. 4, 2022 (CD 2022-0022). These actions approved
modifications to the overall intake and discharge system that facilitate the desalination plant's stand-
alone operation. When originally approved in 2006, the plant functioned in tandem with the adjacent
Encina Power Station. Since the station's decommissioning in 2018, the desalination plant has been
transitioning to stand-alone operations, which requires the phased construction of new facilities,
including the modifications to the overall system, to permit independent operation.
Description of proposed modifications. The DFS structure and the deck are currently approved to
be anchored into the Santiago Formation, a geologic formation underlying the lagoon floor, by
114, 14-to 24-inch precast piles installed using impact hammering. The construction contractor
is concerned that the hardness of the Santiago Formation may prohibit the successful installation
of the piles using the impact-hammer method. If the contractor is unable to drive one or more of
the piles to the correct depth, the pile(s) would have to be abandoned in-place and another pile(s)
would need to be hammered in a different location, resulting in additional disturbance to the
lagoon floor and potential structural design problems.
To avoid this outcome, the contractor is recommending a modification to the construction
methodology that involves drilling and casting-in-place the DFS structure and deck anchor piles
in lieu of the impact hammering. This modification would result in an increase in the diameter of
the cast in place piles (36-inch piles rather than 14-to 24-inch piles) and a reduction in the total
number of piles (67 piles rather than 114 piles). The proposed piles would be constructed in the
same location as the permitted piles. CD 2023-0006 has been filed to request approval of the
modification.
Community Development Department
Planning Division J 1635 Faraday Avenue Carlsbad, CA 92008-7314 J 442-339-2600 www.carlsbadca.gov
CD 2023-0006-CARLSBAD DESALINATION PLANT INTAKE AND DISCHARGE MODIFICATION:
CONSTRUCTION METHOD MODIFICATION REQUEST (DEV2023-0074)
May 18, 2023
Pa e 2
Other than the change to the pile construction method and pile size and number, there is no other project
change.
Findings to approve CD 2023-0006. After careful consideration of the request and consistent with Planning
Division Policy No. 35, the City Planner has determined that the request meets all the findings below and
APPROVES this request.
1) No project condition, feature, facility or amenity is changed or deleted that had been considered
essential to the project's design, quality, safety or function in that the project modifications would
not materially change the desalination plant's. design, function, or appearance. Instead, the
modifications would help facilitate the transition to a stand-alone operation of the Claude
"Bud" Lewis Carlsbad Desalination Plant. Further, instead of the approved construction method
of impact driving pre-cast piles for the DFS structure and deck, the anchors would be placed
using a less impactful, pre-drilling cast in place pile method. Overall, the project would
contribute to the continued safety and function of the facility.
2) The request represents an upgrade in overall design features and/or materials and improves upon
the project's compatibility with the surrounding neighborhood in that project modifications
would be limited to the pile construction method and pile size and number. The modification
would result in wider but substantially fewer piles installed in the same location as the
permitted piles. The DFS structure and deck and other intake and discharge infrastructure are
not readily visible to the public and the pile modifications wou(d not change this.
3) The proposed revisions do not change the density or boundary of the subject property in that
changes would be limited to the pile construction method and pile diameter and number. The
modification would result in wider but substantially fewer piles installed in the same location
as the permitted piles.
4) The proposed revisions do not involve the addition of a new land use not shown on the
original permit in that the changes would be limited to the pile construction method and pile
diameter and number. The modification would result in wider but substantially fewer piles
installed in the same location as the permitted piles.
5) The proposed revisions do not involve the addition of a new land use riot shown on the original
permit in that the project changes would be limited to the pile construction method and pile
diameter and number. Further, the piles would be constructed in the same location as the
permitted piles.
6) The proposed revisions do not rearrange the major land uses within the development in that the
project changes would be limited to the pile construction method and pile diameter and number.
Further, the piles would be constructed in the same location as the permitted piles.
7) The proposed revision do not create changes of greater than ten percent provided that compliance
would be maintained with the applicable development standards of the Carlsbad Municipal Code.
The piles would be constructed in the same location as the permitted piles and, while the
diameter of the piles would increase, the number of piles would decrease. There are no
CD 2023-0006-CARLSBAD DESALINATION PLANT INTAKE AND DISCHARGE MODIFICATION:
CONSTRUCTION METHOD MODIFICATION REQUEST (DEV2023-0074)
May 18, 2023
Pa e 3
appliable Municipal Code development standards, but the modified piles would be consistent
with the 2022 project approvals issued by the city.
8) The proposed changes would not result in any significant environmental impact, and/or require
additional mitigation in that the city has reviewed the scope of the project and has determined
that none of the requirements in CEQA Guidelines sections 15162 or 15163 calling for the
preparation of a subsequent or supplemental E/R have been triggered. The Final EIR and Seventh
Addendum prepared for the Carlsbad Desalination Plant, as supplemented by the Dudek
September 2022 memorandum, have fully analyzed and mitigated, where feasible and in .
compliance with CEQA, all potentially significant environmental impacts, if any, that would
result from the project modifications. Further, the impacts to the environment because of the
modifications are consistent with and would not create substantial new or increased impacts
beyond those that were evaluated in the EIR and Addendum. In fact, the proposed construction
modification would not require pile driving {hammering) for the anchoring of the DFS structure
and deck but would use a less environmentally impactful caisson drilling method. Finally, an
April 19, 2023, Dudek memorandum considered the proposed construction modification
pursuant to CEQA and concluded that none of the proposed construction modification involves
new significant impacts or a substantial increase in previously identified impacts as analyzed in
the Seventh Addendum.
9) The proposed changes would not result in any health, safety or welfare impacts in that th_ey are
consistent with the project description analyzed in the Final EIR and Seventh Addendum, as
supplement-ed by the Dudek September 2022 memorandum.· The project modifications would
not result in any new significant impacts and would remain subject to all applicable mitigation
and agency permits. Further, the proposed construction modification does not involve· new
significant impacts or a substantial increase in previously identified impacts related to the City
of Carlsbad's temporary Fire Station 7 approximately 400-feet south of the project.
10) There were not any major issues or controversies associated with the original project which would
· be exacerbated with the proposed change. The desalination plant's potential impacts to marine
resources through the intake and discharge of seawater were an area of controversy
associated with the original plant approval in 2006. Proposed changes do not alter the plant's ·
fundamental operations and do not increase its use of seawater, flow rate, or the quantity and
quality of discharge. Rather, improvements provide for the desalination plant's continued
operation in compliance with the state's 2015 Ocean Plan Amendment for seawater
desalination facilities; thus, impacts to marine life would remain less than significant.
Other issues raised during the approval of the plant include its energy use and potential
growth-inducing impacts. Proposed changes are not relevant to these issues as they do not
impact the desalination plant's energy use or potable water production.
11) The proposed changes would not be readily discernable to the decision makers as being
substantially different from the project as originally approved in that the project changes would
be limited to the pile construction method and pile diameter and number. The modification
would result in larger but substantially fewer piles installed in the same location as the
permitted piles. The DFS structure and deck are in an area not readily visible to the public.
CD 2023-0006-CARLSBAD DESALINATION PLANT INTAKE AND DISCHARGE MODIFICATION:
CONSTRUCTION METHOD MODIFICATION REQUEST (DEV202370074)
May 18, 2023
Pa e4
NOTICE
Please take NOTICE that approval of your project includes the "imposition" of fees, dedications,
reservations, or other exactions hereafter collectively referred to for convenience as "fees/exactions."
You have 90 days from the date of final approval to protest imposition of these fees/exactions. If you
protest them, you must follow the protest procedure set forth in Government Code Section 66020(a), and
file the protest and any other required information with the City Manager for processing in accordance
with Carlsbad Municipal Code Section 3.32.030. Failure to timely follow that procedure will bar any
subsequent legal action to attack, review, set aside, void, or annul their imposition.
You are hereby FURTHER NOTIFIED that your right to protest the specified fees/exactions DOES NOT
APPLY to water and sewer connection fees and capacity charges, nor planning, zoning, grading or other
similar application processing or service fees in connection with this project; NOR DOES IT APPLY to any
fees/exactions of which you have previously been given a NOTICE similar to this, or as to which the statute
of limitations has previously otherwise expired.
This decision may be appealed by you or any other member of the public to the Planning Commission
within ten days of the date of this letter. Appeals must be submitted in writing to the Planning Division
at 1635 Faraday Avenue in Carlsbad, along with a payment of $847. The filing of such appeal within such
time limit shall stay the effective date of the order of the City Planner until such time as a final decision
on the appeal is reached.
If you have any questions regarding this letter, please contact Scott Donnell, Senior Planner, at (442) 339-
2618.
CITY OF CARLSBAD
MIKE STRONG
Assistant Community Development Director
MS:SD:JC
c: Mark Rohrlick, Cabrillo Power I LLC, 804 Carnegie Center, Princeton, NJ 08540
David Rick, Project Engineer
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