Section 271 - Alternative method of assessment1. Notwithstanding the provisions of the preceding section, if the notice of public hearing to be held by the board of supervisors pursuant to section two hundred fifty-four shall contain a statement that the cost of the improvement will be assessed in proportion as nearly as may be to the benefit which each lot or parcel of land will derive therefrom, and in the case of a water quality treatment district, such cost shall be assessed, levied and collected as hereinafter provided. The board of supervisors may determine to issue, pursuant to the local finance law, the obligations of the county in such an amount as said board may estimate to be sufficient to pay the entire cost of the improvement, but not in excess of the maximum amount proposed to be expended for the improvement as stated in the notice of hearing published pursuant to section two hundred fifty-four. In preparing the annual estimate of revenues and expenditures pursuant to section three hundred fifty-three of this chapter, the administrative head or body shall include, in addition to all costs of operation and maintenance for the next succeeding fiscal year, sums sufficient to pay the annual installment of principal of, and interest on, obligations issued as aforesaid. The administrative head or body shall thereupon annually assess the amount of the estimate of expenditures, less the estimate of revenues as set forth in the estimate so prepared, on the lots and parcels of land in the district in proportion as nearly as may be to the benefit which each lot or parcel will derive therefrom and shall prepare an assessment roll which shall describe each such lot or parcel of land in such manner that the same may be ascertained and identified and shall show the name or names of the reputed owner or owners thereof, and the aggregate amount of the assessment levied upon such lot or parcel of land. The assessment roll shall be submitted to the budget officer at the same time as the estimate is submitted, for transmittal with the tentative budget to the clerk of the board of supervisors. The assessment roll shall remain on file in the office of the clerk and be open to public inspection during business hours. The board of supervisors shall hold a public hearing on the assessment roll. Notice of such public hearing shall be published at least once in the official newspapers stating that said assessment roll has been completed and that at a time and place to be specified therein the board of supervisors will meet and hear and consider any objections which may be made to the roll. The first publication of the notice of the completion of the roll shall be not less than five days before the date specified for the hearing. At the time and place specified, the board of supervisors shall meet and hear and consider any objections to the assessment roll, and may change or amend the same as it deems necessary or just so to do and may affirm and adopt the same as originally proposed or as amended or changed, or they may annul the same and order the administrative head or body to proceed anew and to prepare another roll or the board of supervisors may prepare such new roll. No such amended, changed or new roll shall be adopted unless the board of supervisors shall hold a hearing thereon in the manner and upon the notice prescribed for the original hearing. It shall be the duty of the board of supervisors to levy the sum apportioned to and assessed upon each such lot or parcel of land at the time and in the manner provided by law for the levy of state, county or town taxes. Such sums so levied shall be collected by the local tax collectors or receivers of taxes and assessments and shall be paid over to the county treasurer, or comparable officer or body, in the same manner and at the same time as taxes levied for general county purposes. The county treasurer, or comparable officer or body, shall keep a separate account of such moneys and they shall be used only for purposes of the county district for which collected. Nothing herein shall prevent the public hearing on the assessment roll from being held simultaneously with the hearing on the county budget held pursuant to section three hundred fifty-nine of this chapter. If the cost of establishment of the county district and the providing of an improvement therein has been assessed, levied and collected pursuant to the provisions of this section, then the cost of any improvement made pursuant to section two hundred sixty-eight shall be assessed, levied and collected pursuant to the provisions of this section. If the cost of establishment of the county district and the providing of an improvement therein has been assessed, levied and collected pursuant to the provisions of section two hundred seventy, then the cost of any improvement made pursuant to section two hundred sixty-eight shall be assessed, levied and collected pursuant to the provisions of section two hundred seventy.2. If the cost of establishment of a county sewer district is assessed, levied and collected pursuant to the provisions of this section, then the cost of any street lateral sewers included in the district or constructed as an improvement to it under section two hundred sixty-eight, shall be assessed, levied, and collected from the properties, lots or parcels fronting or abutting thereon. The provisions of this subdivision two shall not apply to the Southwest sewer district, also known as county sewer district number three, in the county of Suffolk.3. In the case of water quality treatment districts, the board of supervisors shall cause to be prepared estimates required to meet expenses for the annual monitoring, testing, operation and maintenance of the district, at the same time as provided in this section for the preparation of the assessment roll. Such annual estimates shall contain the anticipated revenue and expenditures for such district for the ensuing year. It shall also show the amount of expenses which shall be apportioned or charged against each lot or parcel within such district in proportion as nearly as may be to the benefit which each such lot or parcel will derive therefrom. After such annual estimates have been prepared the board of supervisors shall cause a notice to be published in the official newspapers that the same may be examined in the office of the clerk and that a public hearing will be held thereon by the board of supervisors, specifying the time when and the place where such hearing will be held. Such public hearing may be held on the same day as the hearing on the county budget pursuant to section three hundred fifty-nine of this chapter. Such notice shall be published at least five days before such hearing. After such hearing the board of supervisors shall adopt such estimates or it may amend and modify the same. If the amount apportioned against any one parcel is increased after the public hearing, the board of supervisors shall hold another public hearing on like notice. Such annual estimates and the apportionment against each such lot or parcel shall be adopted by the board of supervisors no later than the date of adoption of the annual county budget. After such adoption such annual estimates shall be filed in the office of the county clerk, and the board of supervisors shall levy the amount apportioned to each lot or parcel at the time and in the manner provided by law for the levy of town and county taxes. Such amount so levied shall be collected and enforced at the same time and in the manner that town and county taxes are collected and enforced. Nothing in this section contained shall be construed to prevent the financing, in whole or in part, of expenditures by private sources, grants or by other means.