The Wichita water system serves more than 410,000 people and has a maximum day capacity of about 105 million gallons per day (MGD). Maximum day demand is projected to increase to 173 MGD by 2025. A water distribution system model was developed from existing city geographic information system (GIS) data and imported into H20Map. Major scope items include development of a GIS-based water model, GIS distribution of demands based on street address, verification of model calibration and diurnal curve development, modeling to determine improvements for low pressure areas and service area expansion to meet future demands through 2025, and development of a 20-year capital improvement plan (CIP).
The hydraulic model contains calibration (Year 2004), Year 2010 and Year 2025 scenarios to determine the system’s capability of meeting maximum day, peak hour of the maximum day, minimum hour plus tank replenishment, and maximum day plus fire flow demand for each of the three pressure zones in the city. In order to meet the expanded service area demand and internal improvements for a Year 2025 peak hour demand of 289 MGD, an additional 200 miles of transmission line were added, an existing pressure zone area was increased, two more pressures zones were incorporated, three new major booster pump stations for pressure zone development were located, and a 15-MGD water treatment plant with a 30-MGD high service pump station was integrated. All suggested improvements were optimized to operate with the city’s existing high service pump stations, clearwells and elevated storage.
GIS integration is a major component of water distribution master planning. Burns & McDonnell used Wichita’s existing spatial data to build the foundation for the master planning study. A data warehouse was built from Wichita’s existing data that contained not only the city’s water distribution system, but also parcel, street, land use and customer demand information. The data warehouse was built with one goal in mind: development of a distribution system model. Therefore, the data warehouse was designed to account for all necessary data fields such as pipe size, age and length. Once the water distribution system was built, the parcel and customer information was used to allocate demand throughout the system.
Before importing the distribution system into the H20Map, a “skeletonizing” tool was used inside the GIS to create a network of critical distribution infrastructure. Creating the distribution model in concert with the GIS data ensures that data use and manipulation can be conducted in either software platform. Modeling results can be read in the GIS to allow the city to quickly extract information about pipe capacities and pressures. The centralized data warehouse storage of all the distribution system data will make it possible to use cost-effective GIS software to interact with modeling results and distribution system features. This reduces the need to maintain multiple licenses of costly water modeling specific software packages.
- Master plan
- Hydraulic modeling
- GIS interface
- Field testing
- Future water supply