Quick answer: California C-42 sanitation system contractors (septic tanks, leach fields, sewer laterals) need the $25,000 CSLB license bond and workers' comp once they hire. General liability for septic installation and repair is available from several markets; sewer main and trenching work is underwritten more closely. Pollution liability is usually a separate policy.
C-42 Sanitation System contractors in California — CSLB numbers
CSLB lists 925 active licenses with the C-42 classification (CSLB license file, September 2026). The most are in Los Angeles, Riverside and San Bernardino counties. Many also hold a C-36 Plumbing license (449) or an A license (242).
What CSLB requires
Every active license needs the $25,000 CSLB contractor license bond. LLC licenses also need a $100,000 employee/worker bond and $1M–$5M of liability insurance.
Workers' comp: required as soon as you have an employee, and for every active license from January 1, 2028 (SB 216, as delayed by SB 1455), except joint ventures with no employees.
What underwriters look at
Septic installation vs. pumping and service
Trench depth and shoring
Sewage releases — pollution is usually excluded from GL
Damage to underground utilities
Vacuum trucks and excavators
Workers' comp class codes (WCIRB, effective 9/1/2026)
Code
Description
Rate per $100
6307
Sewer construction — regular hourly wage under $45
$7.451
6308
Sewer construction — $45/hr or more
$4.117
Note: Advisory pure premium rates per $100 of payroll, before each carrier's own rating. Your actual premium depends on the carrier, payroll and experience.
Coverage we quote for this trade
General liability (several markets write this trade)
Commercial auto and hired/non-owned auto
CSLB license bond and contract bonds
Tools and equipment (inland marine)
Umbrella/excess
Workers' compensation: few markets write this trade — call us and we will tell you honestly what is available
What to have ready for a quote
Revenue and payroll; % septic vs. sewer-lateral work
Trench depths
Trucks and equipment
Current policy and losses
Get a quote
Call (858) 925-9555 or request a review online — only your name, phone and email are required; we collect project details by phone. Asena Capital Insurance Services, CA License #6008596.
Frequently asked questions
Does general liability cover a sewage spill?
Usually not — most GL policies exclude pollution. Septic contractors should ask about contractors pollution liability.
What workers' comp code applies to sewer laterals?
Sewer main and lateral construction uses dual-wage codes 6307 (under $45/hr) and 6308 ($45/hr or more). Septic tank installation may classify differently — confirm with the carrier.