Nivelmap
EN

Rio Grande De Loiza at Highway 183 San Lorenzo water level

River gauge, Rio Grande De Loiza, Puerto Rico, United States

Directions

Right now

Very low for mid-October

Water level

7.35ft Steady over the last 24 hours

Flow
35.6 cfs
10 20 30 Highest onrecord 35.62 ft Minor floodstage 14.00 ft

History

History
7.58.08.5ftOct 16Oct 17Oct 18Oct 19Oct 217.58.08.5ftOct 16Oct 18Oct 21
89ftSep 22Sep 29Oct 6Oct 13Oct 2189ftSep 22Oct 6Oct 21
789ftOct 2025Jan 2026Apr 2026Jul 2026Oct 2026789ftOct 2025Apr 2026Oct 2026
789ftJanMarMayJulSepNov2026789ftJanAprJulOct2026

20252026

Water level Normal range (10–90 %) Minor flood stage

What this means

The Rio Grande De Loiza at Highway 183 San Lorenzo is running far below normal at 7.35 ft.

The median for mid-October is 7.77 ft, based on 34 years of readings, so the river stage is 0.42 ft below typical. It is 6.65 ft below the flood stage of 14.00 ft. On the same day last year the reading was 7.44 ft, a difference of −0.09 ft.

It has barely moved over the past 24 hours. Without real rain upstream, that is unlikely to change quickly.

Fall is often low-water season on rivers, and it usually takes a few days of steady rain to change that.

Compared with 34 years of daily readings for this time of year. How to read levels

Key numbers

Median for this date
7.77 ft0.42 ft below the median for this date
Normal for this date
7.38 ft – 8.33 ft8 years in 10 fall in this range (34 years of records)
Same day last year
7.44 ft−0.09 ft
Lowest and highest in 30 days
7.21 ft – 8.39 ft
Lowest and highest in 12 months
7.05 ft – 9.48 ft
Highest on record
35.62 ftSeptember 10, 1996

Floating and fishing near Rio Grande De Loiza at Highway 183 San Lorenzo

Low water exposes gravel bars that make good wading access, but some boat ramps may be left high and dry.

Flood stage here is 14.00 ft, 6.65 ft above the current reading. Beyond it, the National Weather Service also defines moderate and major flood stages.

What happens at each level

18.00 ft
La Marina bridge PR 980 likely to be impassable. oms 3/2023
16.00 ft
Road 181 near Escuela Vocacional Dr. Antonio Fernos Isern flooded. OMS 4/2023
14.00 ft
Rio Loiza out of its banks along road 183./OMS 2/2022
7.35 ft
Right now

Impact statements from the U.S. National Weather Service.

Highest crests on record

RankLevelDate
135.62 ftSeptember 10, 1996
231.37 ftJanuary 5, 1992
330.14 ftSeptember 21, 1998
427.71 ftSeptember 18, 2022
526.74 ftSeptember 15, 2004
624.50 ftSeptember 21, 2008
724.18 ftSeptember 20, 2017
823.67 ftAugust 22, 2001
923.19 ftAugust 23, 2000
1021.81 ftSeptember 20, 1994

Weather at the gauge

Rain in the last 3 days: 0.16 in. Rain that falls upstream can take hours or days to show up at a river gauge.

17 Sat 87° 74° 0.20 in, 90% Wind 7 mph
18 Sun 87° 74° 0.09 in, 100% Wind 6 mph
19 Mon 86° 72° 0.08 in, 100% Wind 7 mph
20 Tue 88° 72° 0.10 in, 93% Wind 6 mph
21 Wed 87° 72° 0.02 in, 66% Wind 8 mph
22 Thu 87° 73° 0.07 in, 74% Wind 9 mph
23 Fri 86° 73° 0.24 in, 51% Wind 8 mph

Forecast: Open-Meteo

Sunrise 06:20 AM Sunset 05:58 PM Daylight 11 hr, 39 min Waxing gibbous 74%

Map

Other gauges on the Rio Grande De Loiza

Gauge Level Compared with normal 24 hours Distance
Rio Grande De Loiza at Quebrada ArenasRiver gauge, Rio Grande De Loiza 5.07 ft Normal −0.03 ft 4.9 mi
Rio Grande De Loiza at CaguasRiver gauge, Rio Grande De Loiza 4.33 ft Very low −0.06 ft 5.0 mi
Rio Grande De Loiza below Loiza DamsiteRiver gauge, Rio Grande De Loiza 2.64 ft Very low −0.11 ft 11 mi

Nearby gauges

Gauge Level Compared with normal 24 hours Distance
Rio Cayaguas at Cerro GordoRiver gauge, Rio Cayaguas 5.92 ft Normal −0.01 ft 2.2 mi
Rio Valenciano near JuncosRiver gauge, Rio Valenciano 2.84 ft Low −0.79 ft 3.1 mi
Rio Gurabo at GuraboRiver gauge, Rio Gurabo 4.40 ft Normal +0.16 ft 5.0 mi
Rio Turabo above BorinquenRiver gauge, Rio Turabo 3.62 ft Very low −0.01 ft 5.4 mi
Rio Gurabo below El MangoRiver gauge, Rio Gurabo 7.69 ft Very low −1.59 ft 6.0 mi
Rio Humacao at Las PiedrasRiver gauge, Rio Humacao 0.42 ft Very low −0.15 ft 6.1 mi
Rio Caguitas at Villa Blanca at CaguasRiver gauge, Rio Caguitas 7.91 ft Normal −0.02 ft 6.1 mi
Rio Bairoa above Bairoa, CaguasRiver gauge, Rio Bairoa 4.20 ft Very low −0.03 ft 7 mi

Questions and answers

Is the Rio Grande De Loiza at Highway 183 San Lorenzo higher than last year?

No, it is 0.09 ft lower than on the same day last year, when the reading was 7.44 ft.

What is flood stage for the Rio Grande De Loiza at Highway 183 San Lorenzo?

The official flood stage is 14.00 ft. The level is currently 6.65 ft below it.

What is a normal level for the Rio Grande De Loiza at Highway 183 San Lorenzo in mid-October?

The median for mid-October is 7.77 ft. In 8 years out of 10 the reading falls between 7.38 ft and 8.33 ft, based on 34 years of records.

Is gage height the same as water depth?

No. Gage height is measured from a fixed reference point chosen by the agency, so a reading of 10 ft does not mean the river is 10 ft deep.

What is the water level of Rio Grande De Loiza at Highway 183 San Lorenzo today?

On Oct 20, 2026, 11:15 PM AST, the water level was 7.35 ft. Steady over the last 24 hours.

Is Rio Grande De Loiza at Highway 183 San Lorenzo rising or falling?

Steady over the last 24 hours. Down 0.20 ft over the last 7 days.

Is the level of Rio Grande De Loiza at Highway 183 San Lorenzo normal?

Very low for mid-October. Compared with 34 years of daily readings for this time of year.

For specialists

Station codes, datum, parameters, data quality and downloads
Operator
U.S. Geological Survey
Station code
usgs:50051800 (Agency page)
Coordinates
18.18571, -65.96145 (WGS84)
Vertical datum
PRVD02
Update interval
every 15 minutes
Licence
Public domain. Data: U.S. Geological Survey (USGS), provisional data subject to revision

Published series

ParameterLast valueTime (UTC)Quality
Water level 7.35 ft 2026-10-21 03:15 Provisional
Flow 35.6 cfs 2026-10-21 03:15 Provisional

Download

Embed this gauge

Add a live card for this gauge to your website. It updates on its own and links back here.

How to cite

U.S. Geological Survey: Rio Grande De Loiza at Highway 183 San Lorenzo (usgs:50051800). Accessed October 21, 2026 via Nivelmap, https://nivelmap.com/en/united-states/puerto-rico/rio-grande-de-loiza-at-highway-183-san-lorenzo

How we check values

Each reading is stored as published. We hold back values that jump faster than physically plausible and show the measurement time with every value.