Regulate Flow of Lake
Lake Lowering Protocol: 8/14/2013
Commission Receives Authority to Manage Lake Level
Annually, the Deal Lake Commission receives a lake lowering permit from the NJ DEP. The objective of this permit is to minimize the risk of property flooding and protect fish and wild life by managing the lake level prior to a rain event greater than 1 inch. NOTE: Coastal flood warnings apply to all low lying Lake Residents and even a lake lowering may not prevent property damage due to tidal surges and rain within the watershed.
Experience has shown that no two rain events are the same and there are many factors that must be considered before determining when to open the gates and when to close the gates. The factors include:
- Amount of rainfall expected in a 24 hour period. http://www.weather.gov/ & http://www.weather.com/
- Additional rainfall beyond the immediate 24 hour period (http://water.weather.gov/precip/?loctype=WFO&loc=wfoPHI)
- Current level of the lake ( as measured at the Flume: Gage on south side; Zero being top of dam
- Watershed saturation from previous precipitation.
- Ocean tide cycle and high tide heights. Easterly or northeast winds will require the flume to be closed 2 hours before and after high tide. Caution must be taken during full moon and coastal flood warnings since the tidal surge could cause more damage than the rain event. The flume during these conditions MUST be closed. http://www.lawrencevilleweather.com/tides/asbury+park+nj
- Wind direction and predicted wind direction shifts (http://forecast.weather.gov/MapClick.php?lat=40.225024210604964&lon=-74.00665283203125)
- Winter ice conditions on lake
- Any Tidal surge above 3.5 feet will result in rising lake levels from ocean water surge that can NOT be controlled by the flume. These waters pour in over the fixed concrete dam which is above the two sluice gates. . http://www.deallake.org/the-flume/
- Sluice gate status. If one gate is under repair or maintenance more time is required for lowering.
If, after taking all these factors into consideration, it is determined the expected rain event has potential for property “structure” flooding , the DLC chairman or his designee will call one of at least three trained operators to open one or both flume gates to facilitate the draw down. Each sluice gate (North/South) can lower the lake by ½ inch per hour. Operators have full authority to open gates if a Flash Flood alert is issued.
Currently, Deal Lake can handle a 1 inch rainstorm with no lowering of the lake from its normal height of about 2 inches above the dam height. A minimum of two commissioners are aware of the weather forecast at all times. Special attention is taken to any local forecast that calls for coastal flooding and heavy rains predicted for our area. These responsible parties determine if the lake needs to be lowered as a precautionary measure prior to, during, or after a rain event.
Rain events between 1 and 2 inches Deal Lake will be taken down to about 2 inches below dam height prior to the rain event. Based on past experience there is no need to “drain the lake for these events. The lake shoreline is covered at this height to protect fish and wildlife and the enjoyment of boaters and others that use the lake..Rain events predicted above 2 inches in a 24 hour period will cause rapid rise in the lake, thus proactive measures to lower the lake below the dam height will take place well prior to the storm arrival and during. A map showing flooding potential from various rain events can be found on te DLC web site.
The gates will be closed when the lake level has dropped to where the risk of flooding has been minimized, high tides will adversely affect the lake, or has met the DEP lowering limit of 12 inches below dam height.
Flume opening and closings can be followed on twitter or via our web site: www.Deallake.org
For more information on flood safety and preparedness, please visit the links below:
National Safety Council | Emergency Preparedness Plan & Checklist
Flood Damage Repair and Clean-Up
Prepare, Plan & Stay Informed for Emergencies
Home Emergency Disaster Safety
Pet Disaster Preparedness – ASPCA
Natural Disasters & Severe Weather
Basic Life Support and Emergency CPR
Public comment is always welcomed on this document via the contact tab of this web site. Thank you.
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