Old and New Modelled for Supply and Emergency

Atlantic City, New Jersey is a popular seaside resort. It lies between New York and Philadelphia, serving the tri-state area of Connecticut, New Jersey and New York. It is on Absecon Island, which has no water supply. The Atlantic City Municipal Utilities Authority (ACMUA) therefore sources all its water from wells on the mainland and treats it there before bringing some 57Ml/day to the island in two 48” mains. Elevated tanks provide water storage. Hazen & Sawyer has a continuing contract since 2005 with the building of a new hydraulic model in InfoWorks WS and continues with the maintenance and use of the model. The InfoWorks model also plays an important role in capital planning process in older parts of the network, as well as ensuring that fire flow pressures are adequate.

Advanced metering
ACMUA has a very advanced water billing system, with automatic meter readings taken through a radio-controlled remote sensing system linked to individually geo-coded customer locations.

Readings are taken approximately every 12 hours, providing near-live consumption figures, which is very useful in comparing demand. ACMUA can judge the consumption and compare it with the water being pumped out from the water treatment plant.
The InfoWorks model is comprehensive - modeling even the smallest pipes - and highly accurate. Hazen & Sawyer took real consumption figures every 12 hours for two week and used the data to calibrate the model.

InfoWorks’ data import capabilities have proved very useful. Of particular help is the facility to import all the individual customer locations. Customer demand was immediately assigned to water distribution nodes. The extensive data available provided an excellent foundation for the model, helping Hazen & Sawyer ensure that the model replicates what happens in practice.

Using the model
The primary role for the InfoWorks model is in ACMUA’s development of a growth strategy to help make daily operations more efficient. This helps to identify where there is water loss, and to make operational decisions.

The tasks for the modeling team are primarily driven by the client’s needs - which currently is the need for more water. There has been a boom in casinos in Atlantic City in recent years together with associated developments such as major shopping malls built on piers extending into the ocean. Hazen & Sawyer is brought in by ACMUA whenever a major development is planned, in order to check out the required infrastructure upgrades and ascertain how much the developer should contribute.
The consultant’s role includes helping to identify the most economical way of accommodating the new casinos. The mains run in a loop system and Hazen & Sawyer works out the optimum point for the connection. The shortest link is not necessarily the best in terms of system hydraulics. Fire protection conditions must also be considered. The advanced fire flow analysis capabilities in InfoWorks are proving ideal for ensuring that sufficient pressures would be maintained in case of fire.

Fighting fire
The InfoWorks model has also been used extensively in checking the city’s fire protection system. In contrast to the ultra-modern wireless metering, there are still some 4” (100mm) pipes dating from the early 20th century. These pipes are very old and very small and cannot supply much fire flow. The team used the InfoWorks hydraulic model to pinpoint any locations where there was insufficient fire flow.

The model showed scattered points across the city where improvements were required. Every year, funding is allocated from an annual budget to target weak points and take remedial action to boost fire flow.