This excerpt taken from the SJW 10-K filed Mar 9, 2007.
Cash and cash equivalents include certain highly liquid investments with remaining maturities at date of purchase of three months or less. Cash equivalents are stated at cost plus accrued interest, which approximates fair value. The cash and cash equivalents balance as of December 31, 2006 was $3,788 which is cash deposited in a bank. The cash and cash equivalents balance as of December 31, 2005 was $9,398 which included $8,397 cash deposited in a bank and $1,001 in short-term investments, consisting primarily of one bond.