When Hurricane Irma disrupted the lives of Floridians last month, many issues were brought to mind that usually go unnoticed in our day-to-day lives. Namely, how does flooding and a widespread loss of power impact our community? What kind of infrastructure is in place to sustain us during a crisis?
Unless you are an engineer, most people don’t usually think about where stormwater runoff goes, how much rainfall a retention pond can hold, or if there are backup power sources in place for lift stations. Our recent hurricane may have caused you to reflect on these issues for the first time. Thankfully, the civil and environmental engineers at Chastain-Skillman enjoy thinking about this every day and always plan for the worst case scenario when creating their designs.
Now that you are thinking about stormwater and wastewater engineering, what are some systems, roads or facilities that impact your everyday life that you may never have thought about before? Some may include Wastewater Treatment Plants, Force Mains, and Lift Stations. But, what exactly are these items? What do they do?
The following are just a few infrastructure projects completed by Chastain-Skillman engineers that you may not know about, as well as a brief explanation for many of these environmental engineering terms.
Florida Polytechnic Lift Stations
Master Lift Station – CS provided services for the intitial infrastructure phase improvements for the university. This included the design of an off-site water main connection, an off-site sewer forcemain (these are needed when the force of gravity is not enough to move wastewater and thus it must be moved by pumps) and on-site lift station (lift stations are where the pumps that move the wastewater are located) to provide water and sewer service for the campus. The proposed infrastructure was sized for the campus at build-out and the water system was analyzed for predicted pressure response under fire flow conditions.
Lift Station No. 2 – CS also provided the design of a lift station that serves the Eastern half of campus and pumps wastewater (at 225 gallons per minute) to the Master Lift Station that serves the entire campus. The pumps are designed to meet future requirements and includes a grinder station in an upstream manhole to reduce incoming solids prior to pumping. At full build out, this facility will serve all the residence halls, Campus Control Center, Admissions Center, Wellness Center Phase 1, and the future Wellness Building.
English Oaks Force Main
CS is currently finishing up the final phase of a multi-phase infrastructure improvement to convey wastewater from the western service area to the City’s Glendale Water Reclamation Facility. This final phase includes the design and construction of over 27,500 ft of force main (force mains are needed when the force of gravity is not enough to move wastewater and thus it must be moved by pumps).
Factors like congested corridors, residential neighborhoods, high groundwater, and areas containing phosphatic clay soils complicate this project. Trenchless installation methods such as jack and bore casings and pilot tube micortunneling (this allows us to install pipelines underneath existing roadways and structures without having to dig a trench) are being utilized to reduce impacts to traffic, residents, and businesses. This project will complete the update to the City’s sanitary sewer system, which has been overloaded due to rapid growth in the western portion of the Lakeland.
Southeast Water Booster Station
CS engineers designed improvements for Lakeland’s Southeast Booster Station (a booster station increases water pressure when it is reduced by either elevation or long distances). The Southeast Booster Station pumps water from the low-pressure zone to the 3.0 million-gallon Highlands Ground Storage Reservoir. Water is then pumped out of the reservoir into the high-pressure zone at increased pressure. The City considered constructing a new reservoir to allow the existing one to be taken out of service for rehabilitation. However, CS utilized the City’s existing water distribution model to create an alternative to constructing a new Ground Storage Reservoir. The alternative involved demolishing the existing Booster Station and replacing it with new booster pumps operating on variable frequency drives. The new booster station will then pump directly into the inlet of the Highlands Ground Storage Reservoir high service pumps, matching the demand of the high-pressure zone. Essentially, this project allows the high-pressure zone to be served by two booster stations operating serially while the existing Ground Service Reservoir is out of service. This booster pumping system supplies both the normal demand and fire protection. CS’s innovative approach saved the City $2.0 million in capital costs.
The improvements included:
- Three 2,100 gallons per minute booster pumps
- Standby generator (Hurricane Irma demonstrated why this is important) and Convault fuel tank, and
- Instrumentation and controls
Crystal Lake Drive
CS provided surveying, design, and permitting services for Crystal Lake Drive improvements in Lakeland. This project encompassed approximately 2,200 lineal feet of roadway along Crystal Lake Drive and the intersection with Lake Hollingsworth Drive. This project included the addition of bike lanes along Crystal Lake Drive with improved drainage infrastructure at the request of the local residents. Corrective milling of the existing roadway was included along portions of the roadway in order to improve both drainage characteristics and to minimize impacts to existing historic trees.
Now that you’ve read a little bit about these projects, it gives you a better understanding of how our water and wastewater systems work in our everyday lives. And when the next crisis occurs, you’ll have a greater appreciation of our city’s unseen infrastructure and for the professionals who can put it back together again.