City officials should know soon whether depositing treated wastewater from the future Civic Center sewage treatment plant underground is environmentally friendly.
By Knowles Adkisson / The Malibu Times
The city is awaiting the results of expensive tests to determine if wastewater treated at the Civic Center wastewater treatment facility scheduled for completion by 2015 would leak into nearby Malibu Creek and Malibu Lagoon if it was deposited in the ground.
“We’re 99.9 percent sure it won’t,” Deputy Building Official Craig George said. “It would be very difficult for water to move toward the lagoon, but we’re confirming that for absolute certainty.”
All businesses in the Civic Center area must cease septic system discharges by 2015 and hook up to the centralized treatment facility as part of a July agreement between the Malibu City Council and the Los Angeles Regional Water Quality Control Board. After passing through the facility, the treated wastewater will qualify as Title 22 effluent that falls short of drinking water standards but is largely harmless to the environment.
The city plans to reuse some of the treated wastewater for irrigation, but it will still have to dispose of excess water by other means. The most likely option is to deposit the water underground. But environmental advocates say the treated wastewater will still possess high levels of nutrients, and must not be allowed to leak into the lagoon or the creek, where it could disrupt aquatic life.
Mark Gold, former president of environmental group Heal the Bay, supports the storage plan, provided the treated water doesn’t filter into the creek or the lagoon.
“I sure hope the study results in demonstrating that the capacity exists in the subsurface for disposal, and that the flow of the groundwater has no potential to bring the high nutrients into the lagoon or the creek,” Gold said.
The city’s goal is to trap treated wastewater between hard bedrock, approximately 140 feet below the surface, and shallower layers of clay.
“We’re just putting it into the aquifer at the lowest level that can receive that amount of water, and then it will be transported into the ocean like all groundwater,” George said.
It is hoped the trapped water would take decades to make it to the ocean.
An engineering firm hired by the city drilled three test wells in the Civic Center area and is tracking the path of water samples. George said city officials should know within a week and a half whether the plan is feasible.
If the tests prove no wastewater will leak into the lagoon or creek, the next step for the city is to commission sonar testing to determine where the undergrounded wastewater would empty into the ocean.
City officials were quick to point out that the drilling process is not the same as deep-well injections, a technique commonly used by petroleum companies which involves drilling as deep as 3,000 feet, then using dynamite to crack the bedrock to release natural gas. Known as “fracking,” the process has been blamed for earthquakes in Ohio and other states.
“We’re not going to any fault zone or bedrock, we’re staying way on top of that,” George said.
So far the city has spent more than $1 million on the study, and George said that figure is expected to rise to $2 million upon completion. The city could potentially apply for state and federal grants to recoup some of the cost if the storage plan is deemed feasible and receives approval by the regional water board, George said.
The total cost to build the Civic Center wastewater facility, according to estimates put forth by the city, range from $30 million to $52 million. The facility will be paid for by an assessment district. The construction of the facility is the first part a three-phase plan outlined in the agreement between the city and the regional board. Facilities for Phases Two (for residential property owners, to be completed by 2019) and Three are also to be paid for by assessment districts. Construction of a sewer for Phase Three is contingent upon water quality studies to be performed following the construction of the Phase One and Two facilities.