萨克拉门托河三角洲的200多个农业排水沟为加利福尼亚州项目用水提供了大量三卤甲烷（THM）前体。据推测，与进入三角洲的主要淡水支流相比，这些排水沟与涉及高度有机泥炭土壤的作物灌溉有关，可能是导致加利福尼亚州三角洲水道中溶解有机碳和THM形成潜力较高的原因。 本研究的目的是评估这一假设。研究发现，与三角洲支流相比，排水沟中的溶解有机物具有更高的分子量和更高的THM活性。包括10个参考文献、表格和图表。

More than 200 agricultural drains in the Sacramento River Delta contribute significant levels of trihalomethane (THM) precursors to California State Project water. It has been hypothesized that these drains, associated with crop irrigation involving highly organic peat soils, are probably responsible for the higher levels of dissolved organic carbon and THM formation potential in the California Aqueduct emanating from the delta in comparison with the principal freshwater tributaries entering the delta. The purpose of this study was to evaluate this hypothesis. It was found that the dissolved organic matter from drains is characterized by a higher molecular weight and greater THM reactivity than that found in delta tributaries. Includes 10 references, tables, figures.