HomeMy WebLinkAboutAvilaRanchBasin1OMP_SOQ_Clean
August 1, 2023
Mr. Nate Stong
Supervising Civil Engineer
Community Development Department
City of San Luis Obispo
nstong@slocity.org
SUBJECT: STATEMENT OF QUALIFICATIONS FOR AVILA RANCH PHASE 1 BASIN A ANALYSIS &
MAINTENANCE RECOMMENDATIONS
Dear Nate,
Rick Engineering Company (RICK) is pleased to provide the following statement of qualifications (SOQ) for
Avila Ranch Phase 1 Basin A Analysis and Maintenance Recommendations, pursuant to your Request for
Qualifications and Interest dated July 19, 2023. This letter includes our project understanding,
qualification, staffing plan, and relevant project examples.
PROJECT UNDERSTANDING
Avila Ranch is a new multi-phase residential development south of downtown San Luis Obispo, near Tank
Farm Road. Phase 1 of Avila Ranch is a single-family home development, featuring several parks and trails.
Vista Park is located in the southwest corner of Tract 3089 (part of Phase 1) and features amenities such
as exercise stations, basketball half-court, play area for children and Basin A. The City of San Luis Obispo
is seeking a qualified team to analyze and prepare a robust Operation and Maintenance Plan (O&M Plan)
prior to assuming the maintenance responsibility of Basin A into perpetuity. A photo of the existing
condition for Basin A was shared in the RFQ and copied here for ease of reference, reflecting what appears
to be long-term ponding and the emergence of cattails within the basin bottom.
Figure 1: Photo of Basin A, Provided by the City of San Luis Obispo
State of Qualifications for Avila Ranch Phase 1 Basin A
August 1, 2023
Page 2 of 4
Upon review of the Phase 1 Grading and Drainage plan prepared by RRM Design Group, and recent photos
included as part of the Request for Qualifications, Basin A is identified as a Bioretention Basin with
infiltration. This suggests that Basin A is not intended to be a Wet Basin with a permanent pool of water.
Bioretention Basins with infiltration are required to drawdown completely after a storm event based on
the infiltration rate of the soil, typically in 24 to 72 hours, and not more than 4 to 7 days to avoid vector-
related issues. In Figure 3 below, a perforated underdrain system is also identified on Section D-D,
indicating it is intended for partial infiltration, and partial biofiltration and release.
Figure 2: Typical Bioretention Basin Detail from Avila Ranch Phase 1 Improvement Plans
Figure 3: Basin Cross Section from Avila Ranch Phase 1 Improvement Plans
There are many factors that may have contributed to the basin’s current state of permanent ponding.
Factors may include sediment from construction activity, sediment-laden flood flows from the adjacent
creek, compaction during construction, missing perforated underdrain system, historically high
groundwater table, issues with the infiltration capability of the underlying native soil, etc. Basin A is
adjacent to Buckley Road and the creek, and there is local and historical knowledge of water ponding in
this area well before the Avila Ranch development. In late 2021, updated geotechnical investigations were
State of Qualifications for Avila Ranch Phase 1 Basin A
August 1, 2023
Page 3 of 4
performed, indicating groundwater was within less than 10 feet below surface. Through various site visits
throughout various seasons of the year, Rick Engineering has visually observed regular ponding within
Basin A.
To better understand the current state of the basin, we would recommend a full reexamination of the
design intent, full review of the design, calculations, and corresponding technical reports. This will allow
for a clearer evaluation of the basin’s current state and functionality, and potential paths forward. Based
on the current knowledge of groundwater and soil properties, we cannot guarantee the outcome of any
possible solutions. We would recommend that further geotechnical investigations be performed to
evaluate the groundwater levels and infiltration rates within the basin footprint to evaluate potential
solutions as they directly impact basin functionality. Potential solutions in regards to the permanent
ponding include: a) performing major maintenance along the bottom footprint to restore the original
intent and ability of the biofiltration soil media and underlying aggregate storage zone to drawdown over
time into the native subgrade, b) adding a forebay to storm drain outlets (i.e. – cobble check dams), c)
providing other forms of pre-treatment via hydrodynamic separators or catch basin inserts, d) scarifying
the bioretention soil, e) adding supplemental infiltration borings to reach soil layers with higher infiltration
rate, f) adding perforated subdrain within aggregate storage layer, and/or g) other, following further
discussion with City staff.
In addition to our Project Understanding outlined above, Rick Engineering has been involved in multiple
aspects of the Avila Ranch project including Phase 1 precise grading plans, Phase 2-6 drainage study peer
review, Phases 3 and 4 developments. This involvement has granted us project familiarity and key history
that will allow a thorough and thoughtful approach to this work.
QUALIFICATION S
RICK has provided stormwater engineering services throughout the central coast region for many years,
and throughout the West for decades. RICK has a comprehensive understanding of the Central Coast Post-
Construction Requirements (PCRs) and has developed multitude of Storm Water Control Plans (SWCP),
Stormwater Control Measure (SCM) Maintenance Agreements and Drainage Studies. This includes design,
construction administration and as-built certification of stormwater control measures (SCMs) such as
bioretention basins, biofiltration basins, infiltration basins, permeable pavers, and underground retention
facilities from conceptual phase to final engineering, including plans, specifications, and cost estimates.
Relevant project examples include:
• West Creek Subdivision, City of San Luis Obispo
• San Luis Ranch, City of San Luis Obispo
• Vinedo/Olsen Ranch, City of Paso Robles
• Grover Beach Train Station Expansion, City of Grover Beach
A key aspect of SCM design involves an as-built verification process, as well as the inclusion of a thorough
O&M Plan to collectively ensure their long-term effectiveness. RICK has a wide array of experience
preparing detailed O&M plans for many landmark projects. Relevant examples include:
• The Orchard at San Luis Ranch O&M Plan, City of San Luis Obispo
• Vinedo/Olsen Ranch SCM O&M Plan, City of Paso Robles
State of Qualifications for Avila Ranch Phase 1 Basin A
August 1, 2023
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• Ashley Falls Regional LID O&M Plan, City of San Diego
• Maple Canyon Restoration Phase 2 O&M Plan, City of San Diego
• Mast Park O&M Plan, City of Santee
PROJECT TEAM
The RICK team for this project is comprised of qualified individuals with an intimate knowledge of local
conditions and directly relevant experience. Our team members include the following personnel:
Tom Martin, PE is an Associate Principal in the San Luis Obispo office of RICK. He has over two decades of
experience managing roadway and civil engineering projects, with 21 years of experience on the Central
Coast. Tom served as the Engineer in Responsible Charge on El Capitan Bridge Replacement and various
Avila Ranch Projects. He is actively involved in Rick projects related to the City of San Luis Obispo.
Brendan Hastie, PE, LEED AP is a Principal of RICK and has more than 20 years of experience in designing
and managing a variety of water resources projects including low impact development (LID), water quality
treatment facilities, H&H analysis, drainage design, flood plain studies, erosion, sediment control, and
hydromodification management. He has developed an excellent reputation among our clients for his
innovative, safe, and cost-effective design solutions. He was an early contributor to the Central Coast
Region’s guidance for Biofiltration Soil Media specifications and has presented on behalf of the Low
Impact Development Initiative (LIDI) in the city.
Shavger Rekani, PE, CFM is an Associate of RICK and has 11 years of experience. He has prepared and
processed projects through various municipal agencies throughout California and numerous resource
agencies. He is very familiar with post-construction and drainage design requirements of various
municipalities in the Central Coast. He was instrumental in the Ashley Falls Regional LID O&M Plan and
Avenida de la Playa O&M Plan.
Ash Paranthaman, PE is a Water Resources Project Engineer and has 7 years of experience. He has
experience preparing Storm Water Control Plans (SWCP), O&M Plans, Hydrologic & Hydraulic studies,
hydromodification management, and floodplain analyses through various municipal agencies within
California and Colorado. He prepared the Vinedo/Olsen Ranch SCM O&M Plan and the Maple Canyon
Restoration Phase 2 O&M Plan.
In addition to the staff above, RICK will provide additional design resources to meet project goals and
achieve a high quality, efficient solution for the City of San Luis Obispo.
On behalf of Rick Engineering Company, we enthusiastically look forward to your invitation to participate
in the information sharing and scoping meeting. Please contact me at (805) 550-0211 or email me at
tmartin@rickengineering.com with regards to this exciting opportunity.
Sincerely,
_____________________________
Thomas E Martin, Associate Principal (PE #64222)
RICK Engineering Company