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Impervious surface cover increases peak fows and degrades stream health, contributing to a variety of hydrologic, water quality, and ecological symptoms, collectively known as the urban stream syndrome. Strategies to combat the urban stream syndrome often employ engineering approaches to enhance stream-foodplain reconnection, dissipate erosive forces from urban runof, and enhance contaminant retention, but it is not always clear how efective such practices are or how to monitor for their efectiveness. In this study, we explore applications of longitudinal stream synoptic (LSS) monitoring (an approach where multiple samples are collected along stream fowpaths across both space and time) to narrow this knowledge gap. Specifcally, we investigate (1) whether LSS monitoring can be used to detect changes in water chemistry along longitudinal fowpaths in response to stream-foodplain reconnection and (2) what is the scale over which restoration eforts improve stream quality. We present results for four diferent classes of water quality constituents (carbon, nutrients, salt ions, and metals) across fve watersheds with varying degrees of stream-foodplain reconnection. Our work suggests that LSS monitoring can be used to evaluate stream restoration strategies when implemented at meter to kilometer scales. As streams fow through restoration features, concentrations of nutrients, salts, and metals significantly decline (p<0.05) or remain unchanged. This same pattern is not evident in unrestored streams, where salt ion concentrations (e.g., Na+, Ca2+, K+) signifcantly increase with increasing impervious cover. When used in concert with statistical approaches like principal component analysis, we fnd that LSS monitoring reveals changes in entire chemical mixtures (e.g., salts, metals, and nutrients), not just individual water quality constituents. These chemical mixtures are locally responsive to restoration projects, but can be obscured at the watershed scale and overwhelmed during storm events