A Change in System Supply and Operations

摘要

For the Texas Gulf Coast, the conversion to surface water is imperative to reduce depletion of aquifers levels that provide the majority of the potable water supply to the region. The Lone Star Ground Water Conservation District has set policy requiring the county's large volume water users to meet various criteria for conversion from groundwater to surface water. The City of Conroe is one of these users, located 40 miles north of Houston, Texas, and has to convert 30% of their usage to surface water by the year 2016 and 61% by the year 2025. The City of Conroe has contracted with a local water authority to receive surface water and is evaluating various surface water take points for optimal usage and system operation. The City has an elevation difference of approximately 170 feet from the northern to the southern end of town, creating challenges in pressure control throughout the water distribution system. The City has developed "pseudo" pressure planes through closing and throttling various manual system valves. To address this, the City would like to develop true pressure planes with a series of automated pressure reducing valves and emergency service valves controlled by SCADA. The City would like to have the pressure planes incorporated into their system by the 2016 surface water conversion Hydraulic modeling, surface water, transmission system, pressure planesdeadline. This system will allow the City to operate the pressure planes with flexibility for the surface water conversion.To plan the conversion and meet the criteria, the City of Conroe retained Lockwood, Andrews, and Newnam (LAN) to provide engineering services and planning strategies and solutions for the surface water conversion. Hydraulic modeling was utilized to analyze the system and plan the integration of surface water into a groundwater system. LAN also developed Design Standards, Specifications, and conceptual Guidelines for the necessary valves and associated SCADA for the City of Conroe's future automated system. This paper will focus on the methods and strategies utilized by the City of Conroe and LAN to plan for the surface water conversion.