Development Impact Fee Nexus Study
City of Cotati
August 12, 2025
What is a Development Impact Fee?
One-time charge 1
Imposed at building permit stage
Imposed on all development projects
within a defined geographic area
Funds facilities to serve new development
2 Mitigation Fee Act Findings (Govt. Code §66001)
§ Key findings
§ Need: Development creates need for facilities
§ Benefit: Development benefits from use of revenue
§ Rough Proportionality: Fee amount development’s
share of facility costs (i.e. proportional to demand)
§ Other findings
§ Purpose of fee
§ Use of fee revenue
3 § Requires local jurisdictions to make certain
information available on website:
§ Current impact fee schedule
§ Nexus studies
§ Annual AB1600 reports
§ Five-Year AB1600 reports
§ Changes to impact fee adoption process:
§ Prior to adoption of development fees,
an impact fee nexus study needs to be
adopted with 30 days notice
§ Technical changes:
§ Residential fees should be charged
per square foot, unless findings are
supported that justify another
metric
§ Large jurisdictions shall adopt a
capital improvement plan as a part
of the nexus study
§ Nexus study should identify level of
service
§ If fees are increasing, review the
assumptions of the original nexus
study and evaluate the amount of
fees collected under the original fee
AB 602
Impact Fees – Basic Methodology
ESTIMATE
EXISTING
DEVELOPMENT
AND FUTURE
GROWTH
IDENTIFY FACILITY
STANDARDS
DETERMINE NEW
FACILITY NEEDS
AND COSTS
ALLOCATE SHARE
TO
ACCOMMODATE
GROWTH
IDENTIFY
ALTERNATIVE
FUNDING NEEDS
CALCULATE FEE BY
ALLOCATING
COSTS PER UNIT
OF NEW
DEVELOPMENT
5 Impact Fee Categories
§Park Facilities
§Traffic Facilities
§General Plan Update
§Water Capacity
§Sewer Capacity
Growth Projections
7 2025 Buildout Increase
Residents 7,281 11,196 3,915
Dwelling Units 3,246 5,349 2,103
Employment 2,615 8,177 5,562
Sources: California Department of Finance, Table E-5, 2025; City of Cotati EIR for the 2013 General Plan Update (2014); Table 2-3 Santero Way Specific Pan Update Draft EIR (2025); OnTheMap Application, http://onthemap.ces.census.gov; Costar; American Community Survey (2023); Table 2.2, Willdan Financial Services.
Cost Allocation Methods:
WHAT Facilities Serve WHO
PLANNED FACILITIES
Planned Facilities
New Demand
BUY IN
Existing Facilities
Total Capacity
EXISTING INVENTORY
Existing Facilities
Existing Demand
SYSTEM PLAN
Existing + Planned Facilities
Total Demand @ Horizon
Fee Program Methodologies
Parks
Existing
Standard
General Plan
System
Plan
Water Capacity
Component
Sewer Capacity
Component
Buy In
Water Capacity
Component
Sewer Capacity
Component
Traffic Mitigation
Planned
Facilities
Major Planned Facilities
§ Share of future General Plan updates
§ Parks needed to maintain existing
standard (4.05 acres per 1,000
residents)
§ Traffic Facilities – Share of various
capacity expanding facilities:
§ Capacity expanding signals
§ Various SR 116 Improvements
§ La Plaza Reunification
§ Bike and Pedestrian Master Plan
§ Safety Improvements
§ Water
§ Future Distribution Facilities
§ Future Storage Facilities
§ Future Well
§ Share of excess capacity in existing
system
§ Sewer Capacity
§ Future Conveyance Facilities
§ Share of excess capacity in existing
system
Maximum Justified Fee Schedule
11 Land Use
Parks and
Recreation
Water
Capacity Sewer Capacity Traffic General Plan Total
Residential - per Square Foot
All Units $ 12.36 $ 4.03 $ 4.91 $ 4.03 $ 0.21 $ 25.54
Nonresidential - per Square Foot
Commercial $ - $ 2.63 $ 3.54 $ 14.56 $ 0.09 $ 20.82
Office - 2.63 3.54 15.26 0.14 21.57
Industrial - 1.09 1.42 8.84 0.05 11.40
Questions
12