Are there fresh water aquifers in Coronado that could be used for a supply of potable water?

It has been stated in recent weeks and over the years that freshwater aquifers, close to the surface, exist in Coronado. There have been stories told and second-hand accounts written, but no studies or documents have been found to confirm that any such aquifers exist. Geologically, this is generally impossible in Coronado, as many areas, including the Golf Course and Tidelands Park, were constructed on hydraulic fill or dredge material, and would not naturally support an aquifer.

Aquifers are geologic formations that contain and support the transmission of groundwater. The near-surface groundwater in the fill areas is tidally influenced and brackish. Brackish water is defined as water with a salinity level of 5 to 30 parts per thousand (water with salinity levels from 30 to 50 is classified as saline, and above 50 is brine). The groundwater in the Country Club area was recently tested and found to have a salinity of 19 parts per thousand.

In 2011, as part of a study considering alternative water sources for irrigation, it was discovered that the golf course pond replenishment well water was seawater strength, and the dry weather groundwater that flows into the underground stormwater system at Coronado Avenue and Eighth Street was brackish. (RBF Consulting City of Coronado Recycled Water Feasibility Study, August 18, 2011)

Current City records do not reveal the presence of freshwater wells.

There are high groundwater levels in Coronado because the City sits mostly at sea level. This groundwater, which when tested is brackish, is often present when excavating construction sites. There is the possibility that small freshwater lenses are present in the fill areas where significant irrigation takes place. Freshwater lenses are thin layers of freshwater that accumulate from rainfall (minimal in Coronado, typically less than 10 inches per year) and irrigation waters that percolate through the soil and rest atop the brackish groundwater. This occurs because of the lower density of freshwater. These lenses, if they do exist, also have not been studied.

Deeper underground reservoirs exist in the greater San Diego area. In our area, there is the San Diego Formation Aquifer. The San Diego County Water Authority said groundwater production is limited by lack of storage capacity, availability of groundwater that makes it into aquifers, and degraded water quality. It said: "Narrow river valleys filled with shallow sand and gravel deposits are characteristic of the most productive groundwater basins in the San Diego region."

Even if Coronado were to find freshwater aquifers under the City, the California Public Utilities Commission has determined that California American Water, an investor-owned utility, has exclusive service rights to provide potable water to customers in Coronado.

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1. What is the plan for addressing sewage coming from Mexico? – EPA has planned several projects to address cross-border sewage.
2. What is the status of funding for the EPA’s plan? – $494 million committed, $130 million still needed.
3. Will the proposed projects result in more raw sewage being discharged to the Ocean? – No! EPA’s plan will improve the status quo.
4. Will EPA’s plan reduce sewage coming from the San Antonio de las Buenos treatment plant further south in Mexico? – Yes! By as much as 95%.
5. Was the Coronado Senior Association moved out of the John D. Spreckels Center to make room for the City’s Cultural Arts senior management analyst?
6. Since the Spreckels Center does not have the word “senior” anywhere on the facility, does the City have a true “senior center” that addresses the needs of those 50 and older?
7. Do I have to recycle my food waste now that EDCO has announced its new Organic Recycling Program?
8. Why does the City waste money watering the synthetic turf at the Lawn Bowling Green?
9. Does the City’s affordable housing provider San Diego Interfaith Housing treat tenants in an arbitrary, unpredictable, discriminatory fashion and evict people without cause?
10. Are the current asphalt repairs simply “make-work” and unnecessary?
11. Are there fresh water aquifers in Coronado that could be used for a supply of potable water?
12. Did the City of Newport Beach successfully challenge a state law, Senate Bill 2, that mandates a city's zoning codes accommodate emergency shelters and transitional housing?
13. Did the new traffic signal at Alameda Boulevard and Fourth Street cause a back-up of traffic east of the intersection on Wednesday, November 6?
14. Does refinancing the former redevelopment agency’s bonds and loans create more density in Coronado?
15. Does the City’s affordable housing provider San Diego Interfaith Housing treat tenants in an arbitrary, unpredictable, discriminatory fashion and evict people without cause?
16. How can the City leave the lights on at the Coronado Public Library overnight especially during the current heat wave and with potential rotating outages?
17. How does a City get selected to Dr. Beach’s Top 10 Best Beaches in America list?
18. Is it true that enterococci bacteria can be caused by decaying kelp and why doesn’t the City think the current advisory at Avenida del Sol is related to sewage impacts from the Tijuana River or Mexico
19. Is the City going to make changes at Coronado Cays Park?
20. Is the City not respecting its beautiful historic sidewalks?
21. Is the City trying to extend San Diego’s Lindbergh Field into Coronado?
22. Is the water quality being affected in South Beach and is Central Beach being tested for the Fourth of July?
23. Is there still time to have a say on the Coronado Cays Park Master Plan?
24. It has been reported in national news stories based on a local report that the City of Coronado’s beach was closed for several weeks. Is that true?
25. Questions have come up in the community about what uses are allowed in the City of Coronado’s R-1A residential zoning code. What are those uses?
26. The City has fire rings at North Beach that get very busy during the summer. What is the City’s fire ring policy? How does the City monitor behavior at the fire rings and is it enough?
27. What are the white cones along the Silver Strand State Highway?
28. Is the National Citizen Survey conducted by the National Research Center valid?
29. What is the current status of the Golf Course Water Recycling and Turf Care Facility project or the environmental review? How are the potential environmental impacts being addressed?
30. What role does the City have in the redevelopment of the Coramart building and has the City prevented its redevelopment?
31. What was the odor in Coronado on Easter Sunday?
32. Why are there two construction sites at Spreckels Park? And why is the site near Seventh only a concrete pad?
33. Why is the City ending its participation in the Rotary Santa program?
34. Why isn’t the City extending service to the Cays this year?
35. Why were two palms recently removed from the beach?
36. Why is the Glorietta Bay Boat Launch Ramp closed and when will it reopen?