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Kazem Alikhani, Director
1221 Elmwood Pk. Blvd., Suite 908
Jefferson, LA 70123
P: (504) 736-6730
F: (504) 736-6835
F: JPDrainagePumpStations@jeffparish.net
Jefferson is a long, narrow Parish (County) in Louisiana, adjacent to the city of New Orleans, reaching from Lake Pontchartrain on the north, about 55 miles south to Grand Isle, on the shores of the Gulf of Mexico. The northern 14 miles of Jefferson is split by the winding Mississippi River into an East and West Bank and this portion of the Parish is considered urbanized, and part of the New Orleans Metropolitan Area. In addition, the Parish is further bounded by estuarine systems of the Gulf of Mexico, at tide level.
Most of the population of Jefferson (nearly ½ Million) is in this urbanized metropolitan area, which has relatively flat topography with ground elevations varying from slightly above to about five (5) feet below sea level. Flood control is provided by a system of levees, floodwalls, canals and drainage pump stations. All stormwater runoff is conveyed by gravity through a system of subsurface drainage lines and canal into the suction bays of various pump stations then pumped into surrounding water bodies outside of the flood protection system.
The Department of Pump Stations is responsible for the operation, maintenance and capital improvement of 47 drainage pump stations containing 130 pumps throughout the Jefferson Parish drainage system. The primary goal of the department is to provide staffing for operations and maintenance of all pumping equipment and associated machinery. All pumping equipment is driven by either electric motor drives some of which are equipped with auxiliary power or diesel engines. Pump station facilities are furnished with a Supervisory Control and Data Acquisition (SDADA) system to provide more efficient response and better control of operation during storm events.
The East Bank has 16 pump stations containing 46 pumps with a total capacity of 15,735 Cubic Feet per Second (CFS). Serving an area of 31,734 acres with a population of 257,501 these facilities provide an average pumping capacity of 0.51 CFS per acre.
The West Bank, exclusive of Crown Point, Lafitte and Barataria, has 17 pump stations containing 64 pumps with a total capacity of 18,849 Cubic Feet per Second (CFS). Serving an area of 48,483 acres with a population of 192,919 these facilities provide an average pumping capacity of 0.39 CFS per acre. Crown Point, Lafitte and Barataria are served by a system of multiple ring-levees and 14 remote lift stations containing 20 pumps with a total capacity of 460 CFS.
The design of pumped drainage systems starts with the return expectancy (or frequency) of various rainfall events. The degree of protection cannot be infinite, but must be related to what the public is willing to support and pay for, as very expensive pump stations, large canals with small slopes, etc. are required. Presently, Jefferson Parishs drainage system provides protection against a 10 year recurrent expectancy.
The design of pumped drainage systems starts with the return expectancy (or frequency) of various rainfall events. The degree of protection cannot be infinity, but must be related to what the public is willing to support and pay for, as very expensive pump stations, large canals with small slopes, etc. are required. Presently, Jefferson Parishs drainage system provides protection against a 10-year recurrent expectancy.
When referring to the capacity of pumps and pump stations, the term CFS is used. CFS stands for Cubic Feet per Second. DFS is one of a number of ways of measuring volumetric flow, and is simply the time it takes for a measured volume to pass a fixed point. For example, a 1000 CFS pump at a pump station can move 1000 cubic feet of water every second from a canal to the other side of a levee.
In order to better appreciate the capacity of a pump station, it is best to use a measure of volumetric flow that everyone understands. Therefore, another more commonly understood term used to measure volumetric flow is GPM, or Gallons Per Minute. In order to compare GPM to CFS, it is essential to know the approximately 7-½ gallons equals 1 cubic foot. Since there are 60 seconds in a minute, 1 CFS equals approximately 7-½ gallons times 60 or almost 450 GPM. This would mean that a 1000 CFS pump moves approximately 450,000 gallons of water every minute!
The entire capacity of Jeffersons pump stations is 35,044 CFS, which translates into almost 16 million gallons of water pumped every minute!
The organization of the department is comprised of administrative, operations and maintenance divisions. Some of the major pump stations are furnished with an operators resident house; other major stations are manned with either two or three eight (8) hour shifts, depending on their locations.
On weekends and holidays, as well as during non-manned periods, pump station operators are placed on stand-by and remain ready to activate the stations at a moments notice should the need arise.
Remote lift stations operate automatically and are inspected daily by the operations division.
Frequently Asked Questions
Q: Are the Pumps turned on?
A: Operation of the pump stations is monitored by the SCADA system. At any given time, the SCADA screen indicates the operational status of all pumps at the stations.
Q: How much rain has fallen?
A: Amount and intensity of rainfall is also monitored by the SCADA system. The SCADA screen indicates incremental and total rainfall at any given time.
Q: Why isnt the water moving in the canals?
A: As the rate of stormwater inflow exceed outflow, in any reach of the canal network, the water rises, occupies more storage and creates the illusion of no flow.
Q: Why arent the pumps on and running before a rainfall event?
A: Water level in the canal system is monitored by the SCADA system. As stormwater arrives at the pump stations, the water level in the suction canals rises and more pumps come on line sequentially.
Q: Why cant we hear the pumps running?
A: Many of the pumps are electric motor driven and run very quietly. Engine driven pumps are housed inside operating buildings and can only be heard near the stations.
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