Los Gatos Stream Gauge 5119 Modification Project
Summary
SCH Number
2026100035
Public Agency
Santa Clara Valley Water District
Document Title
Los Gatos Stream Gauge 5119 Modification Project
Document Type
NOE - Notice of Exemption
Received
Posted
10/1/2026
Document Description
Located in Los Gatos Creek County Park in the town of Los Gatos, Los Gatos Stream Gauge 5119 (Gauge 5119) is used to measure instream bypass flows at the Kirk Diversion Dam established by the Lake and Streambed Alteration Agreement (LSAA) for the Kirk Diversion Operation and Maintenance Project (Notification No. 1600-2018-0386) to support downstream aquatic habitat.
Gauge 5119 is located below a pedestrian bridge and on top of a concrete drop structure on Los Gatos Creek. The existing concrete drop structure is 53 feet long, extends 100 feet across the entire width of Los Gatos Creek, and serves as the weir for Gauge 5119. Flow over the top of the drop structure occurs as shallow sheet flow, and the Gauge 5119 flow readings correlate to the depth of the water on top of the concrete drop structure. Due to the shallow depth of water on top of the concrete drop structure, minor variations in stage (i.e., water surface elevation) result in large changes in flow readings, adversely affecting the accuracy of the flow measurements.
Valley Water proposes installing a 1-foot-tall, 3/8-inch-thick steel weir plate over the top of the existing concrete drop structure. A v-notch in the center of the weir plate would concentrate low flows and produce larger changes in water depth for small variations in flow. This modification would improve the resolution and accuracy of the low flow measurements at Gauge 5119.
A weir box would be affixed to the upstream face of the drop structure at the center of the weir. The weir box would provide hydrographers with a suitable cross section to take accurate discharge measurements for calibrating the stream gauge while reducing field safety hazards and streamlining data collection. A bubbler-type, differential pressure stream gauge enclosed in 1.5-inch-diameter galvanized pipe conduit would extend from the new gauge to an enclosed gauge house with a data
logger above the right top of bank immediately upstream of the drop structure. Solar panels mounted on top of the enclosure would power the system.
Valley Water Standard Best Management Practices (BMPs) and Santa Clara Valley Habitat Plan Aquatic Avoidance and Minimization Measures (Aquatic AMMs) have been incorporated into the project. The BMPs and Aquatic AMMs would protect riparian and aquatic habitat and prevent sedimentation and degradation of water quality in Los Gatos Creek. The project is anticipated to take 3 weeks to complete.
Contact Information
Name
Kelly White
Agency Name
Santa Clara Valley Water District (Valley Water)
Job Title
Associate Environmental Planner
Contact Types
Lead/Public Agency / Project Applicant / Parties Undertaking Project
Phone
Email
Location
Coordinates
Cities
Los Gatos
Counties
Santa Clara
Regions
San Francisco Bay Area
Cross Streets
Dell Ave and Division St (closest cross streets)
Zip
95032
Parcel #
424-09-068
State Highways
SR 85 and Hwy 17
Schools
Farnham Elementary School, Village Elementary School
Waterways
Los Gatos Creek, Oka Percolation Ponds, Camden Percolation Ponds
Township
8S
Range
1W
Section
00
Other Location Info
On Los Gatos Creek, in Los Gatos Creek County Park (station 350+50 to 352+85), under a pedestrian bridge between the Oka Groundwater Percolation Ponds and Camden Groundwater Percolation Ponds
Notice of Exemption
Exempt Status
Categorical Exemption
Type, Section or Code
Class 1 Categorical Exemption: Existing Facilities (CEQA Guidelines Section 15301)
Reasons for Exemption
The project qualifies for a Class 1 (Existing Facilities) Categorical Exemption because the project involves minor alteration of an existing public facility with no expansion of existing or former use. None of the applicable exceptions noted under the CEQA Guidelines §15300.2 that would prevent the project from being exempt apply.
County Clerk
Santa Clara
Attachments
Notice of Exemption
Disclaimer: The Governor’s Office of Land Use and Climate Innovation (LCI) accepts no responsibility for the content or accessibility of these documents. To obtain an attachment in a different format, please contact the lead agency at the contact information listed above. For more information, please visit LCI’s Accessibility Site.