This book details the methodology for the design and construction of flow-measuring facilities such as weirs in Coastal Plain agricultural watersheds. The author was part of a team tasked with this work as part of a large watershed study. The design of these facilities is necessary to accurately and efficiently measure flow rates in the absence of defined channels. Weirs are used to confine flow in these geographical areas. The book describes in detail the model studies carried out to design an optimal weir. This includes how to minimize downstream scour, installation scheduling, necessary site preparation, and other considerations such as potential high water levels and flow submergence. The author also covers the materials, construction techniques, and components of the facilities. This book is a valuable resource for hydrologists and engineers working in similar geographical and hydrological conditions.