Photo: Ryan Hagerty / U.S. Fish and Wildlife Service Opens in a new tab. · Public domain.
No access method is recommended today. Skip this trip for now. Review the conditions below before choosing another reach or day.
Rating updatedRiver local time:
USGS shows 94 cfs. The flow has been stable over about 6 hours. USGS marks this reading provisional and may revise it. USGS records for this date (1995-2025, 31 readings) show a median near 149 cfs and the lower quartile near 102 cfs; today's flow is below normal for the date. USGS 08170500 reports provisional flow and stage for the upper-city reach near Spring Lake Dam, City Park, Rio Vista, and I-35. It does not report current water temperature, clarity, recreation pressure, habitat-closure deployment, or conditions near Martindale and Luling. Use USGS 08171400 for the Martindale corridor and USGS 08172000 for the Luling reach; the three gauges are not interchangeable. This is below normal, so edge depth, temperature, and pressure matter.
NWS air forecast near
This is an air forecast, not a river-temperature reading. Use a short early plan, carry water and sun protection, and leave when heat makes the outing unsafe.
Discharge
Latest reading: 94 cfs. Stable over about 6 hours. Chart covers Sep 5 through Sep 12; readings are provisional and may be revised.
Mostly Clear
The National Weather Service forecast is temporarily unavailable.
Current U.S. Geological Survey gauge: San Marcos River at San Marcos, TX
Seasonal starting points, not a live hatch report. Match what you see on the water.
Match what is actually present. Timing changes with reach, weather, water temperature, flow, and recreation pressure.
Also try Stealth Bomber
Each pictured fly name opens its matching Fly Box guide. These are seasonal planning choices, not a live hatch claim.
Choose one reach, one matching gauge, and one confirmed access. Current clarity, water temperature, crowding, logjams, and posted habitat restrictions still need a day-of check.
Use this chart for not yet confirmed flow and stage near Spring Lake Dam, City Park, Rio Vista, and I-35. Check current clarity, temperature, crowds, and posted habitat restrictions separately.
Use the Martindale gauge for the Retreat, Scull Road, Cottonseed Rapids, and Martindale Dam plan. Do not borrow the upper-city chart.
Use the Luling gauge for the SH 90-to-Zedler route. Low-water snags and logjams can still change after the reading.
Use a short early plan, carry water and sun protection, and leave when heat makes the outing unsafe. No gauge on this page confirms current water temperature, clarity, crowds, or obstruction status.
No access method is recommended in today's conditions. Review the live river and weather checks before making another plan.
Not recommended today. Recheck the river, weather, and access before planning another trip.
Not recommended today. Recheck the river, weather, and access before planning another trip.
Not recommended today. Recheck the river, weather, and access before planning another trip.
This report separates the upper San Marcos city reach from Martindale and Luling. Check the matching gauge, access, heat, recreation pressure, habitat restrictions, and portages before choosing a bank, wade, or float plan.
USGS 08170500 supports the upper-city flow chart from Spring Lake Dam through the San Marcos parks and I-35. It does not report water temperature, clarity, crowding, current habitat-closure deployment, or downstream conditions.
USGS shows 94 cfs. The flow has been stable over about 6 hours. USGS marks this reading provisional and may revise it. USGS records for this date (1995-2025, 31 readings) show a median near 149 cfs and the lower quartile near 102 cfs; today's flow is below normal for the date. USGS 08170500 reports provisional flow and stage for the upper-city reach near Spring Lake Dam, City Park, Rio Vista, and I-35. It does not report current water temperature, clarity, recreation pressure, habitat-closure deployment, or conditions near Martindale and Luling. Use USGS 08171400 for the Martindale corridor and USGS 08172000 for the Luling reach; the three gauges are not interchangeable. This is below normal, so edge depth, temperature, and pressure matter.
The current NWS air forecast is about 83F, and the next 24-hour high reaches about 101F. This is an air forecast, not a water-temperature reading. Use a short early plan, carry water and sun protection, and leave when heat makes the outing unsafe.
A heat alert is active near this forecast point, so the score is capped at caution until water temperature and fish-handling risk are checked. NWS alert: Heat Advisory issued September 11 at 7:51PM CDT until September 12 at 7:00PM CDT by NWS Austin/San Antonio TX.
September through December: Cooling weather can improve the day plan, but the correct gauge, access, rules, and habitat checks still control.
Leave when heat makes the outing unsafe, current or weather turns hazardous, a habitat restriction blocks the plan, an access term is not confirmed, or the float depends on an unverified portage, obstruction, launch, takeout, or shuttle.
Use the matching gauge as trend context, not a universal safe number. Exact-reach access, current, clarity, heat, recreation pressure, habitat restrictions, and the chosen mode still decide the trip.
Leave when heat makes the outing unsafe, current or weather turns hazardous, a habitat restriction blocks the plan, an access term is not confirmed, or the float depends on an unverified portage, obstruction, launch, takeout, or shuttle.
Choose one reach: City Park or Rio Vista with USGS 08170500, Retreat or Scull Road with 08171400, or SH 90 to Zedler with 08172000.
Compare the Guadalupe, Pedernales, or Medina only after checking that river's own live conditions, rules, access, and heat plan.
When: Year-round, with activity changing by weather and reach
Use streamers and surface bugs around legal open-water edges, pools, and cover without entering protected vegetation.
When: Most useful in suitable moving water
The Retreat listing documents Guadalupe bass. Match the Martindale gauge and current access before choosing that reach.
When: Warmwater opportunities through the year
Use smaller flies in open water and avoid disturbing Texas wild-rice or other marked habitat.
When: Middle- and lower-river context
These species can be present, but this page does not claim a current bite or abundance level.
Choose the exact reach first. Then open its current access, gauge, and safety source.
Check the Texas Outdoor Annual rules effective on the date you fish. A valid fishing license and freshwater endorsement generally apply. The 2025–26 rules run through August 31, 2026. The posted 2026–27 limits take effect September 1. Current posted rules and onsite signs control.
| River section and season | Fishing rules |
|---|---|
| Upper citySpring Lake Dam to the city wastewater-treatment plant | This is the State Scientific Area and Texas wild-rice reach. Use USGS 08170500 for flow and stage. At 120 cfs or lower, TPWD may mark fragile areas closed with booms, buoys, or signs. A low reading alone does not confirm whether a closure is deployed. Official rule |
| City Park and Rio Vista | Use named city access and current posted rules. City Park has no river-use reservation or fee, but visitor parking is paid. Rio Vista charges nonlocal adults $5 on the exact posted 2026 dates and has separate local-pass and parking terms. Official rule |
| Retreat, Scull Road, and Martindale | Use USGS 08171400. The Retreat requires a reservation and current fee. Scull Road requires a text for gate code and parking availability. Cottonseed Rapids may require a portage, and Martindale Dam requires one. Official rule |
| LulingSH 90 to Zedler Mill | Use USGS 08172000 for this six-mile designated paddling trail. Public parking is listed at both ends. Low-water snags or logjams may occur, and a dam lies beyond the Zedler takeout. Official rule |
A named public upper-city river entry. The city lists no river-use reservation or fee. Visitor parking is paid, and current river-use rules still apply.
Site detailsA public access at 555 Cheatham Street. Check the dedicated 2026 page for exact $5 nonlocal-adult dates, free youth entry, local-pass eligibility, and affected-weekend parking controls.
Site detailsA TPWD leased-access site open through August 31, 2027. Reservation is required. Current posted fees are $5 for bank fishing and $3 for launch or takeout, with access from 30 minutes before sunrise to 30 minutes after sunset.
Site detailsA TPWD leased takeout for the roughly three-mile Retreat float. Text the listed number before arrival for the gate code and parking availability. Bridge access is loading and unloading only.
Site detailsA six-mile designated route with public parking at both ends. Do not pass the Zedler takeout because a dam lies downstream.
Site detailsOfficial flow, access, habitat, rules, paddling, and weather sources were checked August 24, 2026. No field visit, current clarity reading, or current water-temperature measurement is claimed.
Check what is allowed, where the rule applies, and whether the river is open.
Check the latest river reading and forecast before you leave.
Check public entry points, land rules, and seasonal access changes.
Use these links for stocking, safety, and other local details.
Check what is allowed, where the rule applies, and whether the river is open.
Open the current rules and check the river section, season, and special limits.
Open the current rules and check the river section, season, and special limits.
Open the current rules and check the river section, season, and special limits.
Check the latest river reading and forecast before you leave.
Open this page and check the latest safety advice before your trip.
Open this river reading to check the latest level, flow, and update time.
Open this river reading to check the latest level, flow, and update time.
Open this river reading to check the latest level, flow, and update time.
Check public entry points, land rules, and seasonal access changes.
Open the land or access page, then check signs before you park or enter.
Open the land or access page, then check signs before you park or enter.
Open the land or access page, then check signs before you park or enter.
Open the land or access page, then check signs before you park or enter.
Open the land or access page, then check signs before you park or enter.
Open the land or access page, then check signs before you park or enter.
Open the land or access page, then check signs before you park or enter.
Open the land or access page, then check signs before you park or enter.
Open the land or access page, then check signs before you park or enter.
Use these links for stocking, safety, and other local details.
Open this page for more river information and check when it was last updated.
Open this page and check the latest safety advice before your trip.
Open this page and check the latest safety advice before your trip.
Open this page for more river information and check when it was last updated.
Open this page and check the latest safety advice before your trip.
Open this page for more river information and check when it was last updated.
Open this page for more river information and check when it was last updated.
What was checked: Official USGS, TPWD, city, habitat, access, paddling, rules, and weather sources support this review. The 1974 TPWD river analysis is labeled historical only. BlueStreamFly does not claim a field visit, current water temperature, current clarity, current crowd level, current obstruction inspection, or universal safe-wading flow.
Live measurements and forecasts keep their provider timestamps. Rules, access, and trip guidance use the source-review date shown here. BlueStreamFly planning advice is editorial interpretation, not an agency notice.
First-hand experience: BlueStreamFly does not claim a first-hand visit or local field test for this report unless a real contributor is explicitly named and linked.
The chart uses USGS 08170500 for the upper-city reach near Spring Lake Dam, City Park, Rio Vista, and I-35. Use USGS 08171400 for Martindale and USGS 08172000 for Luling.
No. The three gauges used here report flow and stage, not current water temperature or cloudy water. They also do not confirm crowds, habitat-closure markers, logjams, or access status.
Choose by reach. Bank and protected-edge wading can fit named open access, but upper-river habitat may restrict wading. Float only after the full launch, takeout, shuttle, parking or gate, obstruction, portage, weather, craft, skill, and PFD check passes.
No. Do not wade, drag a craft, or anchor in Texas wild-rice or a marked exclusion area. Follow current booms, buoys, signs, and onsite instructions.
Check the Texas Outdoor Annual rules effective on the date you fish and the posted rules at the access. A valid license and freshwater endorsement generally apply.
