Screen the 100-year daily-mean flood at Fish River, Maine; identify estimator un (47.2375, -68.5827777777778)

Author: AquaScope Studio
Date: 2026-09-27
Description: Screen the 100-year daily-mean flood at Fish River, Maine; identify estimator uncertainty and limitations.
Version: 1.0

Site: 47.2375 N, 68.5828 W

Answer. Screen the 100-year daily-mean flood at Fish River, Maine; identify estimator uncertainty and limitations: 100-year return level, GEV (L-moments) 463.9 m3/s (established). The 100-year return level from 100 annual maxima: GEV by L-moments 463.9 m3/s; Log-Pearson III 445.4 m3/s (90 % confidence interval 404.7 to 490.2 m3/s); bootstrap GEV 458.8 m3/s (90 % confidence interval 400.9 to 514.1 m3/s). Mann-Kendall on the annual maxima: not significant at the 5 % level (p = 0.32, Sen's slope 0.24 m3/s per year over 100 years). The record at Fish River, Maine (usgs USGS-01013500) runs from 1903-07-29 to 2026-09-21 (123.1 years, discharge in m3/s). The two fits differ by 4%.

Key numbers

Quantity Value Unit Step
Record length 123.1 years s1
100-year return level, GEV (L-moments) 463.9 m3/s s1
100-year return level, Log-Pearson III 445.4 m3/s s1
100-year LP3 90 % interval, low 404.7 m3/s s1
100-year LP3 90 % interval, high 490.2 m3/s s1
100-year return level, GEV (MLE with L-moments fallback) 458.8 m3/s s1
100-year GEV bootstrap 90 % interval, low 400.9 m3/s s1
100-year GEV bootstrap 90 % interval, high 514.1 m3/s s1
Q95 (exceeded 95 % of days) 4.67 m3/s s1
Q50 (median flow) 21.9 m3/s s1
Q10 101.0 m3/s s1
Mann-Kendall p-value (annual maxima) 0.3197 s1
Sen's slope 0.24 m3/s per year s1
2-year return level, GEV (L-moments) 233.4 m3/s s1
2-year return level, Log-Pearson III 236.3 m3/s s1
5-year return level, GEV (L-moments) 301.0 m3/s s1
5-year return level, Log-Pearson III 303.9 m3/s s1
10-year return level, GEV (L-moments) 343.3 m3/s s1
10-year return level, Log-Pearson III 343.1 m3/s s1
25-year return level, GEV (L-moments) 394.1 m3/s s1
25-year return level, Log-Pearson III 387.5 m3/s s1
50-year return level, GEV (L-moments) 429.9 m3/s s1
50-year return level, Log-Pearson III 417.6 m3/s s1

Summary

Screen the 100-year daily-mean flood at Fish River, Maine; identify estimator uncertainty and limitations.. The record: Fish River, Maine (usgs USGS-01013500), 123.1 years. 1 step(s) ran (None plan, playbook flood_risk); 5 of 5 gates passed. Screen the 100-year daily-mean flood at Fish River, Maine; identify estimator uncertainty and limitations: 100-year return level, GEV (L-moments) 463.9 m3/s (established).

The decision

Screen the 100-year daily-mean flood at Fish River, Maine; identify estimator uncertainty and limitations: 100-year return level, GEV (L-moments) 463.9 m3/s (established). It holds under these conditions: The annual maxima are independent and drawn from a stationary distribution.; Daily mean maxima can understate instantaneous flood peaks.. Limitations and unresolved checks: Maintainer reproduction; independent hydrologist review pending.; Daily mean maxima are not instantaneous annual peaks or a certified design flood.. The grade applies to primary result and applicable supporting checks.

Findings

- [established] Record length: 123.1 years (from s1.years)
- [established] 100-year return level, GEV (L-moments): 463.9 m3/s (from s1.ffa.fits.gev_lmoments.q.5)
- [established] 100-year return level, Log-Pearson III: 445.4 m3/s (from s1.ffa.fits.lp3.q.5)
- [established] 100-year LP3 90 % interval, low: 404.7 m3/s (from s1.ffa.fits.lp3.ci.5.0)
- [established] 100-year LP3 90 % interval, high: 490.2 m3/s (from s1.ffa.fits.lp3.ci.5.1)
- [established] 100-year return level, GEV (MLE with L-moments fallback): 458.8 m3/s (from s1.ffa.fits.gev_bootstrap.q.5)
- [established] 100-year GEV bootstrap 90 % interval, low: 400.9 m3/s (from s1.ffa.fits.gev_bootstrap.ci.5.0)
- [established] 100-year GEV bootstrap 90 % interval, high: 514.1 m3/s (from s1.ffa.fits.gev_bootstrap.ci.5.1)
- [established] Q95 (exceeded 95 % of days): 4.67 m3/s (from s1.fdc.q95)
- [established] Q50 (median flow): 21.9 m3/s (from s1.fdc.exceedance.44)
- [established] Q10: 101 m3/s (from s1.fdc.q10)
- [established] Mann-Kendall p-value (annual maxima): 0.3197 (from s1.ffa.amax_trend.p_value)
- [established] Sen's slope: 0.24 m3/s per year (from s1.ffa.amax_trend.sens_slope_per_year)
- [established] 2-year return level, GEV (L-moments): 233.4 m3/s (from s1.ffa.fits.gev_lmoments.q.0)
- [established] 2-year return level, Log-Pearson III: 236.3 m3/s (from s1.ffa.fits.lp3.q.0)
- [established] 5-year return level, GEV (L-moments): 301 m3/s (from s1.ffa.fits.gev_lmoments.q.1)
- [established] 5-year return level, Log-Pearson III: 303.9 m3/s (from s1.ffa.fits.lp3.q.1)
- [established] 10-year return level, GEV (L-moments): 343.3 m3/s (from s1.ffa.fits.gev_lmoments.q.2)
- [established] 10-year return level, Log-Pearson III: 343.1 m3/s (from s1.ffa.fits.lp3.q.2)
- [established] 25-year return level, GEV (L-moments): 394.1 m3/s (from s1.ffa.fits.gev_lmoments.q.3)
- [established] 25-year return level, Log-Pearson III: 387.5 m3/s (from s1.ffa.fits.lp3.q.3)
- [established] 50-year return level, GEV (L-moments): 429.9 m3/s (from s1.ffa.fits.gev_lmoments.q.4)
- [established] 50-year return level, Log-Pearson III: 417.6 m3/s (from s1.ffa.fits.lp3.q.4)
- Agrees: spread 4% between 463.9, 445.4 (25% allowed) at T = 100 years
- Agrees: Mann-Kendall on the annual maxima: p = 0.32, tau = 0.07: no trend at the 0.05 level

Problem and decision

Screen the 100-year daily-mean flood at Fish River, Maine; identify estimator uncertainty and limitations. Decision: Screen the 100-year daily-mean flood at Fish River, Maine; identify estimator uncertainty and limitations.. Intake: return_period = 100.

Site and data

Site: 47.2375, -68.5827777777778. No inventory.

Methodology

Objective: Screen the 100-year daily-mean flood at Fish River, Maine; identify estimator uncertainty and limitations..

1. Compare GEV L-moments, LP3 and GEV MLE quantiles on complete-year daily maxima.

Step s1: `flood_frequency(source='usgs', station_id='USGS-01013500', bootstrap_ci=True)`, method at_site_flood_frequency; gates: min_years 20 on ffa.n_years; unit_present on unit; max_return_period_factor 3 on ffa.n_years; spread_within 0.25 on ffa.fits.gev_lmoments.q, ffa.fits.lp3.q; trend_on_series 0.05 on ffa.amax_trend.

Assumptions: Independent stationary annual maxima..

Results: step s1

The record at Fish River, Maine (usgs USGS-01013500) runs from 1903-07-29 to 2026-09-21 (123.1 years, discharge in m3/s). Mann-Kendall on the annual maxima: not significant at the 5 % level (p = 0.32, Sen's slope 0.24 m3/s per year over 100 years). The 100-year return level from 100 annual maxima: GEV by L-moments 463.9 m3/s; Log-Pearson III 445.4 m3/s (90 % confidence interval 404.7 to 490.2 m3/s); bootstrap GEV 458.8 m3/s (90 % confidence interval 400.9 to 514.1 m3/s). The two fits differ by 4%. Flow duration: the flow exceeded on 95 % of days is 4.67 m3/s, the median 21.9 m3/s, the flow exceeded on 10 % of days 101 m3/s. Gates: min_years passed (100 years of record, 20 needed); unit_present passed (unit m3/s); max_return_period_factor passed (T = 100 years against a cap of about 300 years (3 times 100 years of record)); spread_within passed (spread 4% between 463.9, 445.4 (25% allowed) at T = 100 years); trend_on_series passed (Mann-Kendall on the annual maxima: p = 0.32, tau = 0.07: no trend at the 0.05 level).

Return levels of annual maximum discharge at Fish River, Maine (usgs USGS-01013500): GEV (L-moments), Log-Pearson III, GEV (MLE with L-moments fallback) fits with the GEV MLE/L-moments bootstrap 90 % band, and the observed annual maxima at their Weibull plotting positions.

Return levels of annual maximum discharge at Fish River, Maine (usgs USGS-01013500): GEV (L-moments), Log-Pearson III, GEV (MLE with L-moments fallback) fits with the GEV MLE/L-moments bootstrap 90 % band, and the observed annual maxima at their Weibull plotting positions.

Annual maximum discharge at Fish River, Maine (usgs USGS-01013500), 100 years (1904 to 2025).

Annual maximum discharge at Fish River, Maine (usgs USGS-01013500), 100 years (1904 to 2025).

Annual maximum discharge at Fish River, Maine (usgs USGS-01013500) with the Sen slope line; the Mann-Kendall test on the annual maxima finds no trend (p = 0.320, 100 years).

Annual maximum discharge at Fish River, Maine (usgs USGS-01013500) with the Sen slope line; the Mann-Kendall test on the annual maxima finds no trend (p = 0.320, 100 years).

Return levels at Fish River, Maine (usgs USGS-01013500) by return period, with the confidence band.

T estimator unit estimate lower upper interval_method confidence_level
2 gev_lmoments m3/s 233.3828
5 gev_lmoments m3/s 301.044
10 gev_lmoments m3/s 343.338
25 gev_lmoments m3/s 394.0839
50 gev_lmoments m3/s 429.8805
100 gev_lmoments m3/s 463.9272
2 lp3_log_moments m3/s 236.3042 224.1971 249.0651 variance_of_estimate 0.9
5 lp3_log_moments m3/s 303.8977 285.5826 323.3874 variance_of_estimate 0.9
10 lp3_log_moments m3/s 343.0796 319.488 368.4132 variance_of_estimate 0.9
25 lp3_log_moments m3/s 387.5232 356.9803 420.6793 variance_of_estimate 0.9
50 lp3_log_moments m3/s 417.5643 381.8784 456.585 variance_of_estimate 0.9
100 lp3_log_moments m3/s 445.3895 404.6771 490.1978 variance_of_estimate 0.9
2 gev_mle_with_lmoments_fallback m3/s 234.7098 222.7553 246.047 nonparametric_bootstrap_percentile 0.9
5 gev_mle_with_lmoments_fallback m3/s 302.8586 285.5962 317.9906 nonparametric_bootstrap_percentile 0.9
10 gev_mle_with_lmoments_fallback m3/s 344.483 319.6619 365.1152 nonparametric_bootstrap_percentile 0.9
25 gev_mle_with_lmoments_fallback m3/s 393.4015 357.1478 424.0718 nonparametric_bootstrap_percentile 0.9
50 gev_mle_with_lmoments_fallback m3/s 427.217 379.8743 468.2861 nonparametric_bootstrap_percentile 0.9
100 gev_mle_with_lmoments_fallback m3/s 458.8331 400.8806 514.057 nonparametric_bootstrap_percentile 0.9

Annual maxima at Fish River, Maine (usgs USGS-01013500).

year value
1904 237.0
1905 88.0
1906 240.0
1907 220.0
1930 263.0
1931 145.0
1932 208.0
1933 273.0
1934 309.0
1935 219.0
1936 227.0
1937 193.0
1938 159.0
1939 303.0
1940 245.0
1941 240.0
1942 300.0
1943 240.0
1944 157.0
1945 236.0
1946 222.0
1947 306.0
1948 160.0
1949 161.0
1950 208.0
1951 243.0
1952 241.0
1953 257.0
1954 260.0
1955 309.0
1956 137.0
1957 172.0
1958 334.0
1959 160.0
1960 286.0
1961 377.0
1962 125.0
1963 248.0
1964 142.0
1965 83.3
1966 162.0
1967 181.0
1968 237.0
1969 351.0
1970 260.0
1971 300.0
1972 292.0
1973 442.0
1974 310.0
1975 300.0

Spread between the GEV and Log-Pearson III return levels at Fish River, Maine (usgs USGS-01013500).

T GEV LP3 spread_pct
2.0 233.3828 236.3042 1.2
5.0 301.044 303.8977 0.9
10.0 343.338 343.0796 0.1
25.0 394.0839 387.5232 1.7
50.0 429.8805 417.5643 2.9
100.0 463.9272 445.3895 4.1

Limitations and what this study does not establish

No failed or skipped checks are recorded; the scope and caveats below still apply.

Caveats, verbatim from the playbook:
- Maintainer reproduction; independent hydrologist review pending.
- Daily mean maxima are not instantaneous annual peaks or a certified design flood.
- No catchment regulation, channel topology or model/gauge comparability was established.
- Re-run live uses current observations; use the retained CSV and this script for reproduction.

Caveats

- Maintainer reproduction; independent hydrologist review pending.
- Daily mean maxima are not instantaneous annual peaks or a certified design flood.
- No catchment regulation, channel topology or model/gauge comparability was established.
- Re-run live uses current observations; use the retained CSV and this script for reproduction.

Recommendations

- Adopt this as the answer to the decision: Screen the 100-year daily-mean flood at Fish River, Maine; identify estimator uncertainty and limitations: 100-year return level, GEV (L-moments) 463.9 m3/s (established).
- Quote both point estimates and only each estimator's own available interval: spread 4% between 463.9, 445.4 (25% allowed) at T = 100 years.
- Read the numbers with this caveat: Maintainer reproduction; independent hydrologist review pending.
- Read the numbers with this caveat: Daily mean maxima are not instantaneous annual peaks or a certified design flood.
- Read the numbers with this caveat: No catchment regulation, channel topology or model/gauge comparability was established.

References

1. England et al. (2019) Bulletin 17C
2. Hosking, J. R. M. (1990). L-moments: analysis and estimation of distributions using linear combinations of order statistics. J. R. Stat. Soc. B, 52(1), 105-124.
3. Vogel, R. M., & Fennessey, N. M. (1994). Flow-duration curves I: new interpretation and confidence intervals. J. Water Resour. Plann. Manage., 120(4), 485-504.
4. England, J. F. Jr. et al. (2018). Guidelines for determining flood flow frequency, Bulletin 17C. USGS Techniques and Methods 4-B5.
5. Mann, H. B. (1945). Nonparametric tests against trend. Econometrica, 13, 245-259
6. Sen, P. K. (1968). J. Am. Stat. Assoc., 63, 1379-1389.
7. Rekin226 and contributors. AquaScope Hydrology 0.19.0 [Software]. Release DOI: https://doi.org/10.5281/zenodo.22930129. All versions: https://doi.org/10.5281/zenodo.21903143. Analysis software revision: 0a7dd68; the release DOI does not archive later code changes.

Appendix: reproducibility

Re-run the same steps with no model: `aquascope run study.yaml`. Resume the workspace: `aquascope studio --resume workspace.json`.

Model: none via none; ledger: no model calls. aquascope 0.19.0.

```yaml
# An AquaScope study (version 3): the plan behind an answer, its gates, and what happened.
# aquascope run study.yaml
version: 3
title: "Daily-mean flood screening: Fish River, Maine"
question: "Screen the 100-year daily-mean flood at Fish River, Maine; identify estimator uncertainty and limitations."
created: "2026-09-27T04:21:19+00:00"
aquascope_version: "0.19.0"
author: "hand"
problem:
kind: "flood_risk"
site: {"lat": 47.2375, "lon": -68.5827777777778}
params: {"return_period": 100}
plan:
playbook: "flood_risk"
objective: "Screen the 100-year daily-mean flood at Fish River, Maine; identify estimator uncertainty and limitations."
caveats: ["Maintainer reproduction; independent hydrologist review pending.", "Daily mean maxima are not instantaneous annual peaks or a certified design flood.", "No catchment regulation, channel topology or model/gauge comparability was established.", "Re-run live uses current observations; use the retained CSV and this script for reproduction."]
methodology: ["Compare GEV L-moments, LP3 and GEV MLE quantiles on complete-year daily maxima."]
assumptions: ["Independent stationary annual maxima."]
steps:
- tool: "flood_frequency"
id: "s1"
method: "at_site_flood_frequency"
arguments:
source: "usgs"
station_id: "USGS-01013500"
bootstrap_ci: true
expects:
- {"check": "min_years", "path": "ffa.n_years", "value": 20}
- {"check": "unit_present", "path": "unit"}
- {"check": "max_return_period_factor", "path": "ffa.n_years", "value": 3, "return_period": 100}
- {"check": "spread_within", "paths": ["ffa.fits.gev_lmoments.q", "ffa.fits.lp3.q"], "value": 0.25, "return_period": 100}
- {"check": "trend_on_series", "path": "ffa.amax_trend", "value": 0.05}
results:
s1: {"ok": true, "gates": [{"check": "min_years", "passed": true, "detail": "100 years of record, 20 needed"}, {"check": "unit_present", "passed": true, "detail": "unit m3/s"}, {"check": "max_return_period_factor", "passed": true, "detail": "T = 100 years against a cap of about 300 years (3 times 100 years of record)"}, {"check": "spread_within", "passed": true, "detail": "spread 4% between 463.9, 445.4 (25% allowed) at T = 100 years"}, {"check": "trend_on_series", "passed": true, "detail": "Mann-Kendall on the annual maxima: p = 0.32, tau = 0.07: no trend at the 0.05 level"}], "summary": "source=usgs, station_id=USGS-01013500, variable=discharge, unit=m3/s, years=123.1, start=1903-07-29, end=2026-09-21", "fallback_used": false, "sha256": "389524192c7d33ec"}
```

Result identities (also in findings.json and the Findings worksheet):
- 100-year return level, GEV (L-moments): result s1.ffa.fits.gev_lmoments.q.5; estimator gev_lmoments; annual maxima of daily mean discharge; years with at least 292 observed days. Input usgs/USGS-01013500, discharge, m3/s, 1903-07-29 to 2026-09-21; content sha256:735990f72ac655a5dbd68aae19e42a769abbcf9eb95747702bb582f7ff4d642c. Software 0.19.0; revision 0a7dd68. Archive revision not recorded; content hash is not an archive DOI. No interval for this estimator.
- 100-year return level, Log-Pearson III: result s1.ffa.fits.lp3.q.5; estimator lp3_log_moments; annual maxima of daily mean discharge; years with at least 292 observed days. Input usgs/USGS-01013500, discharge, m3/s, 1903-07-29 to 2026-09-21; content sha256:735990f72ac655a5dbd68aae19e42a769abbcf9eb95747702bb582f7ff4d642c. Software 0.19.0; revision 0a7dd68. Archive revision not recorded; content hash is not an archive DOI. Own interval [404.6771, 490.1978], method variance_of_estimate, level 0.9.
- 100-year return level, GEV (MLE with L-moments fallback): result s1.ffa.fits.gev_bootstrap.q.5; estimator gev_mle_with_lmoments_fallback; annual maxima of daily mean discharge; years with at least 292 observed days. Input usgs/USGS-01013500, discharge, m3/s, 1903-07-29 to 2026-09-21; content sha256:735990f72ac655a5dbd68aae19e42a769abbcf9eb95747702bb582f7ff4d642c. Software 0.19.0; revision 0a7dd68. Archive revision not recorded; content hash is not an archive DOI. Own interval [400.8806, 514.057], method nonparametric_bootstrap_percentile, level 0.9.
- 2-year return level, GEV (L-moments): result s1.ffa.fits.gev_lmoments.q.0; estimator gev_lmoments; annual maxima of daily mean discharge; years with at least 292 observed days. Input usgs/USGS-01013500, discharge, m3/s, 1903-07-29 to 2026-09-21; content sha256:735990f72ac655a5dbd68aae19e42a769abbcf9eb95747702bb582f7ff4d642c. Software 0.19.0; revision 0a7dd68. Archive revision not recorded; content hash is not an archive DOI. No interval for this estimator.
- 2-year return level, Log-Pearson III: result s1.ffa.fits.lp3.q.0; estimator lp3_log_moments; annual maxima of daily mean discharge; years with at least 292 observed days. Input usgs/USGS-01013500, discharge, m3/s, 1903-07-29 to 2026-09-21; content sha256:735990f72ac655a5dbd68aae19e42a769abbcf9eb95747702bb582f7ff4d642c. Software 0.19.0; revision 0a7dd68. Archive revision not recorded; content hash is not an archive DOI. Own interval [224.1971, 249.0651], method variance_of_estimate, level 0.9.
- 5-year return level, GEV (L-moments): result s1.ffa.fits.gev_lmoments.q.1; estimator gev_lmoments; annual maxima of daily mean discharge; years with at least 292 observed days. Input usgs/USGS-01013500, discharge, m3/s, 1903-07-29 to 2026-09-21; content sha256:735990f72ac655a5dbd68aae19e42a769abbcf9eb95747702bb582f7ff4d642c. Software 0.19.0; revision 0a7dd68. Archive revision not recorded; content hash is not an archive DOI. No interval for this estimator.
- 5-year return level, Log-Pearson III: result s1.ffa.fits.lp3.q.1; estimator lp3_log_moments; annual maxima of daily mean discharge; years with at least 292 observed days. Input usgs/USGS-01013500, discharge, m3/s, 1903-07-29 to 2026-09-21; content sha256:735990f72ac655a5dbd68aae19e42a769abbcf9eb95747702bb582f7ff4d642c. Software 0.19.0; revision 0a7dd68. Archive revision not recorded; content hash is not an archive DOI. Own interval [285.5826, 323.3874], method variance_of_estimate, level 0.9.
- 10-year return level, GEV (L-moments): result s1.ffa.fits.gev_lmoments.q.2; estimator gev_lmoments; annual maxima of daily mean discharge; years with at least 292 observed days. Input usgs/USGS-01013500, discharge, m3/s, 1903-07-29 to 2026-09-21; content sha256:735990f72ac655a5dbd68aae19e42a769abbcf9eb95747702bb582f7ff4d642c. Software 0.19.0; revision 0a7dd68. Archive revision not recorded; content hash is not an archive DOI. No interval for this estimator.
- 10-year return level, Log-Pearson III: result s1.ffa.fits.lp3.q.2; estimator lp3_log_moments; annual maxima of daily mean discharge; years with at least 292 observed days. Input usgs/USGS-01013500, discharge, m3/s, 1903-07-29 to 2026-09-21; content sha256:735990f72ac655a5dbd68aae19e42a769abbcf9eb95747702bb582f7ff4d642c. Software 0.19.0; revision 0a7dd68. Archive revision not recorded; content hash is not an archive DOI. Own interval [319.488, 368.4132], method variance_of_estimate, level 0.9.
- 25-year return level, GEV (L-moments): result s1.ffa.fits.gev_lmoments.q.3; estimator gev_lmoments; annual maxima of daily mean discharge; years with at least 292 observed days. Input usgs/USGS-01013500, discharge, m3/s, 1903-07-29 to 2026-09-21; content sha256:735990f72ac655a5dbd68aae19e42a769abbcf9eb95747702bb582f7ff4d642c. Software 0.19.0; revision 0a7dd68. Archive revision not recorded; content hash is not an archive DOI. No interval for this estimator.
- 25-year return level, Log-Pearson III: result s1.ffa.fits.lp3.q.3; estimator lp3_log_moments; annual maxima of daily mean discharge; years with at least 292 observed days. Input usgs/USGS-01013500, discharge, m3/s, 1903-07-29 to 2026-09-21; content sha256:735990f72ac655a5dbd68aae19e42a769abbcf9eb95747702bb582f7ff4d642c. Software 0.19.0; revision 0a7dd68. Archive revision not recorded; content hash is not an archive DOI. Own interval [356.9803, 420.6793], method variance_of_estimate, level 0.9.
- 50-year return level, GEV (L-moments): result s1.ffa.fits.gev_lmoments.q.4; estimator gev_lmoments; annual maxima of daily mean discharge; years with at least 292 observed days. Input usgs/USGS-01013500, discharge, m3/s, 1903-07-29 to 2026-09-21; content sha256:735990f72ac655a5dbd68aae19e42a769abbcf9eb95747702bb582f7ff4d642c. Software 0.19.0; revision 0a7dd68. Archive revision not recorded; content hash is not an archive DOI. No interval for this estimator.
- 50-year return level, Log-Pearson III: result s1.ffa.fits.lp3.q.4; estimator lp3_log_moments; annual maxima of daily mean discharge; years with at least 292 observed days. Input usgs/USGS-01013500, discharge, m3/s, 1903-07-29 to 2026-09-21; content sha256:735990f72ac655a5dbd68aae19e42a769abbcf9eb95747702bb582f7ff4d642c. Software 0.19.0; revision 0a7dd68. Archive revision not recorded; content hash is not an archive DOI. Own interval [381.8784, 456.585], method variance_of_estimate, level 0.9.

Cite this software

Rekin226 and contributors. AquaScope Hydrology 0.19.0 [Software]. Release DOI: https://doi.org/10.5281/zenodo.22930129. All versions: https://doi.org/10.5281/zenodo.21903143. Analysis software revision: 0a7dd68; the release DOI does not archive later code changes.


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