As in 2017, many private water wells were flooded by hurricanes and their aftermath this year.
The 2018 Atlantic hurricane season, typically considered the period from June 1 through November 30, has been “above-average,” according to experts in mid-October. The season is the first on record to see six subtropical storms.
On September 5, Hurricane Florence became the first major hurricane of the season and wettest tropical cyclone recorded in North Carolina and South Carolina. Just more than one month later, Michael became the second major hurricane of the season on October 7, hitting the Florida Panhandle with significant rainfall, also reaching southern Georgia, and dumping more rain in the Carolina counties already affected by Florence. Michael was the strongest on record in the Florida Panhandle and later became the fourth-strongest landfalling hurricane in the contiguous Untied States in terms of wind speed.
Considering both hurricanes, potentially 730,000 or more private wells in North and South Carolina as well as Florida, Georgia, Alabama, and Virginia may have been affected by the effects of flooding, high water table connection to septic systems, flood debris damage, or related incidents, according to the U.S. Census Bureau’s 1990 Household Water Supply Survey.
The following numbers of private wells (drilled and dug) were tabulated for counties with disaster designation or receiving 5 or more inches of rainfall during Florence and Michael:
- North Carolina —351,936
- South Carolina — 134,595
- Georgia — 91,513
- Florida — 69,673
- Virginia — 50,685
- Alabama — 32,787
- Total — 731,189.
To derive these numbers of wells, state county maps of disaster designation were overlain with National Weather Service rainfall intensity maps to identify the counties and wells potentially affected, according to Chuck Job, NGWA regulatory affairs manager, who compiled this data. Additional adjacent counties may have had significant flooding from lesser rainfall amounts that also impacted wells.
The 1990 Household Water Supply Survey is the last one to track all counties.
“Areas potentially affected by high water tables from heavy rainfall can cause communication between septic systems and wells from saturated subsurface conditions that can be a significant health issue, similar to surface flooding with potential contaminants moving down wells and along well casings,” Job says.
Following a flood, disinfection and wellhead repair may be common needs among well owners. Well relocation and elevation may be other services offered. NGWA recommends water well system professionals be used to assess and service wells.
In addition, in areas of private wells with known flooding potential in the spring, summer, and fall of each year — such as low-lying coastal areas, and river and creek valleys — contractors can work with state and county agencies, and local media, to alert well owners to their services and inform them of actions they can take before and after flooding to protect their groundwater supply.
NGWA has a resource center on hurricanes and groundwater housed on its website for consumers, WellOwner.org. Included is information on how to protect well systems before and after the storm.
NGWA also has other resources contractors may find helpful in dealing with flooded water wells including the best suggested practice Residential Water Well Disinfection Following a Flood Event: Procedures for Water Well System Professionals and a Water Well Journal® article titled “Responding to Flooded Wells” at WellOwner.org/hurricane-resources.