Gum Bayou at FM 646 water level
City of League City gauge 5320 · Gum Bayou · published on the Harris County Flood Warning System
water surface elevation, Oct 21, 2026 at 3:48 PM CDT · 32 minutes ago
- Below top of bank
- 9.9 ft
- Top of bank
- 11.5 ft
- Lowest since Oct 21
- 1.58 ft
- Highest since Oct 21
- 2.19 ft
This gauge has been recorded here since October 21, 2026 (15 readings so far). Its usual range and how today compares with its history appear once it has 14 days of readings.
Last 7 days
Hourly averages of readings as published. This gauge reports only when its value changes, so gaps in the line are normal.
| Time | Level | Below top of bank |
|---|---|---|
| Oct 21, 3:00 PM CDT | 1.61 ft | 9.9 ft |
| Oct 21, 2:00 PM CDT | 1.84 ft | 9.7 ft |
| Oct 21, 1:00 PM CDT | 1.84 ft | 9.7 ft |
| Oct 21, 12:00 PM CDT | 1.92 ft | 9.6 ft |
| Oct 21, 11:00 AM CDT | 1.96 ft | 9.5 ft |
| Oct 21, 10:00 AM CDT | 2.03 ft | 9.5 ft |
| Oct 21, 9:00 AM CDT | 2.19 ft | 9.3 ft |
How to read this gauge
The number above is an elevation, not a water depth. It is the height of the water surface above a fixed reference level, so FM 646 reads around 2 ft even when the channel is low. What matters is the distance to the top of bank: the elevation at which water reaches the top of the channel at this location. For this gauge that is 11.5 ft.
The bottom of the channel here sits at -0.4 ft, so the channel is roughly 11.9 ft deep at this crossing. City of League City publishes the top-of-bank figure with each reading; it is their reference, not an estimate made here.
Daily highs and lows since October 21, 2026
Download the readings
gum-bayou-at-fm-646.csv (CSV): every reading stored for this gauge since October 21, 2026, 15 rows, updated with this page. Columns: time in UTC, time in Central, water surface elevation, top of bank, and distance below top of bank, all in feet. The source and accuracy notes below apply to the file too.
Put this gauge on your website
HOAs, MUDs, civic clubs and schools can show this gauge's latest reading on their own site. Paste this HTML where it should appear; the card updates with this page. More gauges.
Other gauges on Gum Bayou
Readings from the rest of the Gum Bayou gauge network, each at its own most recent reading. Elevations fall as the channel runs downstream, so compare the below top of bank column rather than the raw levels.
| Crossing | Level | Below top of bank | Reading taken |
|---|---|---|---|
| Bishops Bridge | 3.29 ft | 7.9 ft | Oct 21, 2026 at 3:59 PM CDT |
All City of League City gauges: City of League City water levels.