A long-awaited survey of groundwater levels and fluctuations beneath the Santa Rosa plain was previewed to a keenly interested group of about 3 dozen stakeholders Thursday morning.

USGS Hydrologist Tracy Nishikawa presents research about groundwater in the Santa Rosa plain.The area under study reaches from above Healdsburg south to Cotati, and from the Santa Rosa foothills west across the Laguna to near Sebastopol. Some critics of the process have charged that those boundaries were drawn to accommodate political considerations, but Tracy Nishikawa, a research hydrologist for the US Geological Survey in San Diego, says the lines were based on geological considerations.

Studying possible future scenarios for water use has obvious applications for years when supplies grow scarce, but Jay Jasperse, Chief Engineer for the Sonoma County Water Agency, notes it will also be useful for flood control planning.