Alert: Sacramento River Weirs Overtopping: SacPAS Sacramento Prediction and Assessment of Salmon and other fishes

Alert: Sacramento River Weirs Overtopping

Data Courtesy of CDEC; Forecast Data Courtesy of National Water Prediction Service (NWPS)

River Stage (Feet) Above / Below Weir Crest Level, Today & Last 10 Days (10/07/2025 - 10/16/2025)
with Daily Average of NWPS Forecasts issued 2025-10-17
Weir	NWPS Forecast 10/21	NWPS Forecast 10/20	NWPS Forecast 10/19	NWPS Forecast 10/18	10/16	10/15	10/14	10/13	10/12	10/11	10/10	10/09	10/08	10/07
MLW	< -0.50	< -0.50	< -0.50	< -0.50	< -0.50	< -0.50	< -0.50	< -0.50	< -0.50	< -0.50	< -0.50	< -0.50	< -0.50	< -0.50
CLW	< -0.50	< -0.50	< -0.50	< -0.50	< -0.50	< -0.50	< -0.50	< -0.50	< -0.50	< -0.50	< -0.50	< -0.50	< -0.50	< -0.50
TIS	< -0.50	< -0.50	< -0.50	< -0.50	< -0.50	< -0.50	< -0.50	< -0.50	< -0.50	< -0.50	< -0.50	< -0.50	< -0.50	< -0.50
FRE	-17.59	-17.58	-17.57	-17.57	-17.55	-17.58	-17.41	-17.34	-16.87	-16.31	-15.82	-15.53	-15.49	-15.28

Below Crest	Crest	Flood	Danger	Peak Value in Period	Within 1 ft of Flood	Peak Value & Within 1 ft of Flood

Water Year 2026 Daily Average River Stage

WY 2026 Sacramento River Weirs Moulton, Colusa, Tisdale, and Fremont, Days Crested: MLW 0, CLW 0, TIS 0, FRE 0, with Daily Average of NWPS Forecasts issued 2025-10-17

Weir Metadata and River Forecasts
Weir	Moulton Weir (MLW)	Colusa Weir (CLW)	Tisdale Weir (TIS)	Fremont Weir (FRE)
River Stage Levels	Minimum: 75.7 Crest: 76.2 Flood: 83.8 Danger: 84.8 Datum: NAVD88	Minimum: 60.4 Crest: 60.9 Flood: 70.1 Danger: 71.1 Datum: NAVD88	Minimum: 43.6 Crest: 44.1 Flood: 51.6 Danger: 52.6 Datum: NAVD88	Minimum: NA Crest: 32.0 Flood: 39.5 Danger: 40.5 Datum: NAVD88
Summary for 10/07/2025 - 10/16/2025	Peak: Below Minimum Crest: 0 Days Flood: 0 Days Danger: 0 Days	Peak: 59.50 on 2025-10-07 Crest: 0 Days Flood: 0 Days Danger: 0 Days	Peak: Below Minimum Crest: 0 Days Flood: 0 Days Danger: 0 Days	Peak: 16.72 on 2025-10-07 Crest: 0 Days Flood: 0 Days Danger: 0 Days
Site History Last Date	Over Crest: 2025-02-18 Over Flood: Over Danger:	Over Crest: 2025-02-23 Over Flood: 1999-04-22 Over Danger:	Over Crest: 2025-03-24 Over Flood: 2000-04-15 Over Danger: 1999-05-24	Over Crest: 2025-02-25 Over Flood: 1997-01-04 Over Danger: 1984-08-21
National Water Prediction Service	River Forecast at Moulton	River Forecast at Colusa	River Forecast at Tisdale	River Forecast at Fremont
California Nevada River Forecast Center River Forecast	River Forecast at Moulton	River Forecast at Colusa	River Forecast at Tisdale	River Forecast at Fremont

Water Year 2026 Daily Data Sacramento River Weirs Moulton, Colusa, Tisdale, and Fremont
WY2026	Moulton Weir MLW Minimum: 75.7 Crest: 76.2 Datum: NAVD88			Colusa Weir CLW Minimum: 60.4 Crest: 60.9 Datum: NAVD88			Tisdale Weir TIS Minimum: 43.6 Crest: 44.1 Datum: NAVD88			Fremont Weir FRE Minimum: NA Crest: 32.0 Datum: NAVD88
WY2026	Daily Avg	Ft above Crest	Ft above/ below Flood	Daily Avg	Ft above Crest	Ft above/ below Flood	Daily Avg	Ft above Crest	Ft above/ below Flood	Daily Avg	Ft above Crest	Ft above/ below Flood
NWPS Forecast 2025-10-21	76.10			60.80			44.00			14.41
NWPS Forecast 2025-10-20	76.10			60.80			44.00			14.42
NWPS Forecast 2025-10-19	76.10			60.80			44.00			14.43
NWPS Forecast 2025-10-18	76.10			60.80			44.00			14.43
2025-10-16				59.50						14.45
2025-10-15				59.50						14.42
2025-10-14				59.50						14.59
2025-10-13				59.50						14.66
2025-10-12				59.50						15.13
2025-10-11				59.50						15.69
2025-10-10				59.50						16.18
2025-10-09				59.50						16.47
2025-10-08				59.50						16.51
2025-10-07				59.50						16.72
2025-10-06				59.50						16.95
2025-10-05				59.50						17.08
2025-10-04				59.50						16.95
2025-10-03				59.50						16.77
2025-10-02				59.50						16.70
2025-10-01				59.50						16.70

WY 2026 Total Days: 16
MLW Crest Days: 0 (0.00 %); Flood Days: 0; Danger Days: 0
CLW Crest Days: 0 (0.00 %); Flood Days: 0; Danger Days: 0
TIS Crest Days: 0 (0.00 %); Flood Days: 0; Danger Days: 0
FRE Crest Days: 0 (0.00 %); Flood Days: 0; Danger Days: 0

Overtopping History at Weirs

Data Notes

At Tisdale, Moulton, and Colusa weirs, there is a minimum stage height to collect data. In the absence of data, the value is assumed below the stated minimum for the weir.
Data is River Stage reported in Feet. Daily value is 24 hour average.
Data Source: California Data Exchange Center
Fremont Weir: On October 3, 2016, the California Department of Water Resources (DWR) changed the reporting of river stage data collected at 5 locations in the lower Sacramento River area from their previous datum, either National Geodetic Vertical Datum 1929 (NGVD29) or United Stated Engineering Datum (USED) to the North American Vertical Datum 1988 (NAVD88) standard.
Moulton, Colusa, Tisdale weirs: On October 1, 2019, the California Department of Water Resources (DWR) changed the reporting of river stage data collected at 21 locations in the upper Sacramento River and Feather River area from their previous datum, either National Geodetic Vertical Datum 1929 (NGVD29), United States Engineering Datum (USED), or Local Datum to the North American Vertical Datum 1988 (NAVD88) standard.

Subscribe to Alerts

To subscribe to the SacPAS Weir Alert email, please email web@cbr.washington.edu with the subject "SacPAS Weir Alert Subscription". At this time, subscribing and unsubscribing to the alert is a manual process.

Emails are generated once daily at 9:15 am on days where the daily average river stage value for "yesterday" is greater than the crest level at least 1 of the 4 weirs being monitored or the NWPS Forecast is greater than the crest level.

Sample email content for 22 December 2021:

ALERT

NWS Forecast: Tisdale (TIS) on 12/25 to crest minimum 44.1: + 0.44 ft.

WY 2022 (82 Days) Summary
Moulton (MLW) Crest Days: 0 (0.00 %) Flood Days: 0 Danger Days: 0
Colusa (CLW) Crest Days: 0 (0.00 %) Flood Days: 0 Danger Days: 0
Tisdale (TIS) Crest Days: 3 (3.66 %) Flood Days: 0 Danger Days: 0
Fremont (FRE) Crest Days: 0 (0.00 %) Flood Days: 0 Danger Days: 0

To see full analysis, please refer to "Alert: Sacramento River Weirs Overtopping" on SacPAS website. 
URL: www.cbr.washington.edu/sacramento//data/alert_weirs.html


Thank you,
SacPAS Web Team
===============
This is automatic email generated by analysis at 22 Dec 2021 09:15:02 PST
Replies to this email go unanswered.