Office Assistant Senior salary at Contra Costa Water District

The average office assistant senior salary at Contra Costa Water District was $167,089 , which is 111 percent higher than the average salary for this job in California, and 161 percent higher than the national average for this job . Office Assistant Senior salaries at Contra Costa Water District typically range from $162,939 to $169,173 (25th to 75th percentile). The highest reported office assistant senior salary was $179,883. There are 11 employees at Contra Costa Water District with the job title office assistant senior.