Flood Stage Estimate for Green Valley Creek @ Diablo Road GVD on Green Valley Creek, Danville
Flood stages have been determined for the stream gauge called Green Valley Creek @ Diablo Road. The plot on the right shows the latest stage data with horizontal lines for the gauge stages at locations in the table below. Green Valley Creek @ Diablo Road is located east of the lower Diablo Blvd crossing of Green Valley Creek near Richard Ln. Flood Stage Report and Maps. Gauge Location Link Please report flooding location and time: Report Flooding from Green Valley Creek
FLOOD STAGES Readings at the gauge that could indicate flooding at the location.
Flooding Order	Gauge Stage	Flooding Locations
4th	9.2	350' down stream of 2nd crossing of Diablo Road  | 850' up stream of 1st (southern) crossing of Diablo Road
3rd	8.4	Green Valley Court | Buchanan Lane | E of Sorrel Court | E of Sorrel Court | 600' and 800' up stream of 2nd (northern) crossing of Diablo Road
2nd	7.6	400 ' up stream of 2nd Northern crossing of Diablo Road   | Diablo Road - 1st Southern Crossing
1st	7.4	Near Donna Lane | Liahona Lane | 260' E of Sorrel Court | Green Valley Pool
How was the flood stage developed?	Computer Model A HEC-RAS Model was made using LiDAR, survey data and some as-built plans. Flows were estimated using USGS StreamStats.
Certainty of flood stage accuracy?	We have 80% confidence in the model results. LiDAR quality in the creek area is degraded by tree cover, making some terrain data unreliable. Additional surveying would improve accuracy, but funding was unavailable for that work. The survey data reflected differences in the channel bottom since the date the LiDAR was flown in approximately 2008. We did not survey every bridge. To be fully confident in the model we would need to survey the entire creek reach.   LiDAR stands for Light Detection and Ranging. It's a technology that uses laser light to measure distances.
Future Efforts	The FC District may send postcard information to properties along the creek. This could include information on how they can help fine-tune the flood stage by reporting where and when flooding is experienced.
View Green Valley Creek @ Diablo Road flood stages: GVD Direct Plot Link.
Please report flooding location and time: Report Flooding from Green Valley Creek
Click here for Flood Stage Report and Maps

Date: 4/21/2025 16:28:57

File location: G:\fldctl\Hydrology\Streamflow\Flood Stage Web Docs\AA-Merge_HTML.docm