本文回顾了迄今为止新罕布什尔州小型供水系统采用的过滤方法，这些系统采用地表水源，并提供了解决该问题的成本概况。到目前为止，新罕布什尔州的大多数小型系统都选择了慢砂过滤和常规过滤。对施工、运营和维护成本的审查有助于在其他水系统中做出未来的技术选择。对目前在小型水系统运行的过滤装置的检查，以及对现有和拟建装置的成本分析，说明了在类似运行条件下，其他小型水系统可能产生的成本。 新罕布什尔州小型供水系统采用的过滤方法符合地表水处理规则的性能标准，其复杂程度与现场特定条件相适应。所研究的每种过滤方法的成本涵盖范围很广，并且似乎随着工厂规模和现场特定条件的不同而有显著差异。本文所研究的成本表明，在1.0 mgd及以下容量的工厂中，慢砂过滤或压力陶瓷过滤通常比包装常规过滤提供更低的施工和运行成本。

This paper reviews methods of filtration implemented to date at small New Hampshire water systems which draw from surface sources and provides a profile of costs incurred in addressing this issue. Slow sand filtration and package conventional filtration are the methods chosen at a majority of small New Hampshire systems to date. A review of construction and operation and maintenance costs lends perspective in making future technical choices at other water systems. The examination of filtration plants currently operating at small water systems plus analysis of costs for both existing and proposed plants has illustrated costs which could be incurred at other small water systems under similar operating conditions. Filtration methods implemented at small New Hampshire water systems meet the performance standards of the Surface Water Treatment Rule with a level of complexity appropriate to the site-specific conditions. Costs for each filtration method examined cover a wide range and appear to vary significantly with plant size and site-specific conditions. The costs examined here indicate that slow sand filtration or pressure ceramic filtration generally offer lower construction and operating costs than package conventional filtration in plants of 1.0 mgd capacity and less.