Environmental Vandalism : Cluster of Vernal Pools in San Marcos Is Sprayed With Herbicide

Vernal pools in San Marcos that were rescued from extinction by environmentalists last year have been vandalized with herbicides and four-wheel-drive vehicles.

The vernal pools, shallow clay-soil depressions that catch spring rainwater and bloom briefly with seasonal and endangered plants, have been drained, sprayed with herbicides and damaged by a four-wheel drive vehicle that drove through the smaller pools in an attempt to eradicate them.

County agricultural department staff members took water and soil samples at the site Thursday to determine if there was an illegal application of pesticide and if the vandalism poses a threat to humans. County hazardous materials crews will be called in to assess the situation and remove any contaminated soils if a danger exists, according to Bill Snodgrass, assistant agricultural commissioner.

Jon Otten of the San Marcos Wildlife Management Network discovered the vandalism last week and alerted the Corps of Engineers, federal Fish and Wildlife authorities and San Marcos city officials.

The government agencies will meet next week on the site off San Marcos Boulevard at Pacific Street to determine what can be done.

Last May, construction on a $75-million County Water Authority aqueduct was halted when a San Diego Biodiversity Project ecologist presented proof that the pipeline would have destroyed a part of the vernal pool cluster.

Otten said the 30-acre site has about 35 to 40 vernal pools. The pools range in size from a small pond to an indentation no larger than an auto tire, but all contain significant plant life, including at least two species listed on the state’s endangered species list. The state-listed endangered species, both candidates for federal listing, are button celery (Eryngium aristulatum) and Orcutt’s brodiaea (Brodiaea orcuttii).

The County Water Authority’s Michael Stift, supervising engineer at the Escondido office, said that water authority studies had cleared the project of environmental impacts last year but that additional environmental documentation provided in May by Biodiversity biologist David Hogan prompted water authority officials to change their plans and tunnel under the vernal pool site to leave the surface undisturbed.

The 286-foot aqueduct tunnel under the vernal pool field will cost $698,000, two to three times more than a trenching operation would have cost, Clift said. CWA officials said the vandalism will not change the authority’s plans to tunnel beneath the habitat.

Otten said the new attack on the vernal pools was “a deliberate attempt to destroy this sensitive area.” However, most of the plants will survive, he said, “because these are very hardy varieties that can survive almost anything.”

Jerry Backoff, San Marcos planning director, said the vernal pool area has been designated by the city as a “resource conservation area” where studies will have to be made to protect the habitat if development is proposed.

Backoff added that he felt Otten was “overreacting to this situation.”

“We could request that the property owners fence in the property, but we don’t have the authority to order them to fence in the site,” he said.

However, Otten said he is worried that people might wander onto the site, damaging the pools.

“This is a very attractive playground for children,” he said.