Daily Analysis

Date: 2026-02-27 (Day -1, pre-study baseline)

1. PRECIPITATION SUMMARY

No precipitation anywhere in the watershed. All 37 HUC12s reported 0.0 inches across all time windows (1hr, 3hr, 6hr, 12hr, 24hr). Gauge-mounted rain sensors at Pruitt, St. Joe, Harriet, and Bear Creek all recorded 0.0 inches. The 7-day antecedent precipitation field was not populated for this day (empty object), so we cannot quantify prior wetness.

2. GAUGE RESPONSES

No significant responses at any gauge. All gauges show flat, baseflow-recession behavior:

• Boxley: Height 2.04 → 2.01 ft over 12 hours. Gradual 0.03 ft decline. No discharge data available (height-only gauge). This is normal baseflow recession.
• Ponca: Discharge 94.9 → 92.0 cfs. Slight decline (~3 cfs). Well below "Too Low" threshold of 150 cfs. The discharge values cluster tightly around 93-95 cfs, consistent with baseflow.
• Pruitt: Height 3.54–3.58 ft (0.04 ft range, noise). Discharge 78.3–84.6 cfs, centering ~81–83 cfs. Below "Too Low" threshold of 100 cfs.
• St. Joe: Height 3.51–3.57 ft (0.06 ft range, noise). Discharge 190–211 cfs, trending slowly down toward ~197 cfs by end of day. Just within the low end of "Optimal" (200–8000 cfs), straddling the "Low but Floatable" boundary.
• Richland Creek: Height 0.99–1.05 ft (0.06 ft range). A minor bump at 18:30–19:30 (1.04–1.05 ft) followed by a quick drop back to 0.99–1.00 ft. This 0.05 ft fluctuation with zero QPE is likely sensor noise or very minor diurnal groundwater variation. Not a rainfall response.
• Bear Creek: Height 2.34–2.37 ft (0.03 ft range). Discharge 7.7–9.3 cfs. Very low flow, essentially flat.
• Harriet: Height 3.63–3.66 ft (0.03 ft range). Discharge 215–228 cfs, declining slightly through the day. Just inside "Optimal" range (200–9370 cfs).

3. RAINFALL-RESPONSE PAIRS

None. Zero precipitation across the watershed.

4. DOWNSTREAM PROPAGATION

Not applicable — no event to propagate.

5. MULTI-DAY EVENTS

Not applicable — no prior day data available and no precipitation today.

6. ANOMALIES OR SURPRISES

Baseflow relationships worth noting for calibration:

At zero-precipitation baseflow, the discharge relationships are: - Ponca (390 km² cumulative): ~93 cfs → specific discharge = 0.24 cfs/km² - Pruitt (513 km² cumulative): ~81 cfs → specific discharge = 0.16 cfs/km²

This is interesting — Pruitt shows lower discharge than Ponca despite draining a larger area. This is likely a rating curve artifact, karst losses in the Pruitt reach, or different groundwater contributions. Need to watch whether this relationship persists. If Pruitt consistently reads lower than Ponca at baseflow, the Ponca-to-Pruitt reach may be a losing section (karst).

• St. Joe (1,932 km² cumulative): ~197 cfs → specific discharge = 0.10 cfs/km²
• Harriet (2,775 km² cumulative): ~215 cfs → specific discharge = 0.08 cfs/km²
• Bear Creek (239 km²): ~8.5 cfs → specific discharge = 0.04 cfs/km²

The declining specific discharge downstream is expected for karst terrain at baseflow — larger basins have more karst losses and longer residence times. Bear Creek's very low specific discharge (0.04 cfs/km²) may indicate significant karst losses in that basin.

Richland Creek baseline: Height ~1.0 ft at baseflow. This is a useful reference point — the March 2024 reference event took this gauge from ~30 cfs (presumably near this height) to ~17,000 cfs. Today's 1.0 ft reading establishes a dry-season baseline.