This excerpt taken from the WTR DEF 14A filed Apr 2, 2009.
Tax Withholding. We have the right to require that grantees pay to us an amount necessary for us to satisfy our federal, state or local tax withholding obligations with respect to grants. We may withhold from other amounts payable to a grantee an amount necessary to satisfy these obligations. We may permit a grantee to satisfy our withholding obligation with respect to grants paid in shares of Aqua America Common Stock by having shares withheld, at the time the grants become taxable, provided that the number of shares withheld does not exceed the individuals minimum applicable withholding tax rate for federal, state and local tax liabilities.