Timmons Group currently provides professional services to the City of Norfolk Department of Public Works under a term contract for stormwater infrastructure, watershed modeling and master planning, drainage improvement design and other general infrastructure improvements. Under this term contract, Timmons Group provided stormwater inventory, watershed modeling and master planning for the area near Azalea Garden Road and Norcova Avenue. The project area consists of three watersheds and covers nearly 400acres. The ultimate purpose of the project was twofold. First, it was to inventory the existing stormwater infrastructure in three watersheds that adjoin in this area. Secondly, it was to develop a stormwater model that evaluates the performance of the existing stormwater infrastructure system during various storm events (2, 5 and 10 year storms).
As part of this project, Timmons Group developed a mobile technology application (StormCollect) compatible with GPS handheld devices to aide in the field inventory and assessment of stormwater infrastructure. This technology application allowed for the very efficient collection of consistent data that was uploaded seamlessly into the City GIS database. We also used the inventory data to develop a very detailed hydraulic model of the separate storm sewer system for each of the three watersheds. We are currently using the model to develop a watershed master plan that will address water quantity improvements and water quality retrofits. Ultimately this work will be used to assist the City of Norfolk with NPDES MS4 permit compliance requirements.