L.A. Firm Seeks to Extend Corona’s Boundaries : Borders: SIC Corp.’s proposal, which could lead to the city’s annexation of land to the south and east, is likely to be challenged by Riverside.

CORONA —  A controversial expansion of the city’s eastern boundaries has led to a proposal that could ultimately extend Corona’s reach thousands of acres farther to the south and east.

Los Angeles-based SIC Corp. has proposed enlarging Corona’s “sphere of influence” to include nearly 5,000 acres south of Cajalco Road and east to the shore of Lake Mathews.

The move is the first in a long process that could lead to Corona’s annexation of the unincorporated, rural and agricultural land and the development of a master-planned residential community.

But the proposal could lead to even more of a fight than the city’s successful two-year battle to add Eagle Valley to its borders: Environmentalists say that the land is a rich kangaroo rat habitat, and Riverside County officials say that it could threaten public works projects, including an expansion of the El Sobrante landfill.

The proposed expansion comes on the brink of the annexation of 2,600 acres to the immediate southeast of Corona that includes a 3,000-home development in Eagle Valley.

That annexation, to be made official in about four weeks, has been key in making it possible for Corona to expand east toward Lake Mathews and south into Temescal Valley along Interstate 15.

But just as there was a bitter fight over the Eagle Valley annexation, the SIC Corp. proposal is expected to face as much or greater opposition. Even though “spheres of influence” only give cities the right to review and comment on development, it is generally regarded as a map of where the city’s boundaries will be in the coming decades.

Increasingly, sphere-of-influence decisions are becoming more vital to cities in western Riverside County.

“The spheres are very important,” Corona Councilman William J. Franklin said. “They give direction to the community involved, its plans and the future.”

In this case, Corona could find its most forceful opponent in the city of Riverside. The SIC Corp. property lies within Riverside’s sphere, and Riverside city officials have fought hard against attempts to change some of the boundaries in the past.

“There’s been some tensions as to where the borders should be,” said Riverside Councilman Ronald Loveridge.

Although he had not heard of the proposal, Loveridge said that Riverside has been interested in keeping Lake Mathews in its sphere.

“Lake Mathews is an extraordinary resource, whether it be visual or something else,” he said.

But SIC Corp. officials have told Corona planners they prefer their city over Riverside because public services such as police and fire protection would be closer, said Deanna Elliano, Corona’s senior planner. In addition, runoff water goes toward the Temescal Wash, making it more efficient to install sewers, city officials said.

Still, regardless of which city’s sphere the property is in, residents of rural communities near Lake Mathews are wary of any move that would lead to massive, higher-density development. Corona city officials say that preliminary development concepts call for primarily single-family homes with an average density of three homes per acre. By contrast, some homes in those communities sit on lots as big as 10 acres.

“This has been brewing for quite some time,” said Art Cassel, a resident of Mockingbird Canyon, which is north of Lake Mathews. “To bring an urban area into one of the last remaining remnants of a rural community is bizarre. . . . You get the high-density development, made even worse because the (Riverside) freeway is overcrowded.”

Residents have turned out in droves to protest any attempts they believe would interfere with their rural lifestyle in an area heavy in citrus groves alongside mountainous ridgelines.

“Corona has made a mad dash for available land,” said Bill Reeves, a resident of the Gavilan Hills community southeast of Lake Mathews. “It’s alarming to us. . . . Most of us have fled from the pressures of Orange and Los Angeles counties.”

SIC Corp. also will have to overcome a host of environmental obstacles. Some of the flattest and most developable land is habitat for the kangaroo rat, which is on the federal endangered species list. The grassy brushland is also suitable for the California gnatcatcher, which is a candidate for the list.

In addition, Riverside County waste management officials have opposed nearby urban development, fearing that it would threaten plans for two public works projects, including a proposed expansion of the El Sobrante landfill and creation of a compost facility south of Cajalco Road east of Interstate 15. County officials say that a residential development could limit the buffer they would have for expanding the site.

“Usually there is only one reason to change your sphere of influence, and that is to promote development,” said Robert Nelson, director of the County Waste Management Agency. “It’s premature to think of urbanizing the area. We just feel that (residential development) should not occur near the landfill for some time to come.”

If the Riverside County Local Agency Formation Commission approves the sphere-of-influence proposal when it comes before the commission in about six months, SIC Corp. is expected to conduct an environmental impact report, which could outline how the company would make up for any destruction of the environment or increase in traffic.

Even with the drawbacks, some Corona council members say that the area will benefit from increased government services and that the city overall will have a more stable tax base. They also point to high-density developments elsewhere in the county that have been buffered from rural areas.

What’s more, some council members say they fear that the land will be developed anyway, creating a ragtag of poorly planned, unincorporated islands.

“If we don’t let Corona develop we will have a series of county islands in our sphere,” said Councilman Franklin. “It will not be a cohesive community.”