Susquehanna River at Harrisburg, Dauphin County PA (HARP1)
Gage Location: Dauphin County, PennsylvaniaSite Location: Dauphin County, Pennsylvania
Latitude: 40.255Longitude: -76.886Elevation: 290.01 ft. MSLDrainage Area: 24100 Sq. Mi.
Minor Stage: 17 ft. Moderate Stage: 20 ft.Major Stage: 23 ft.
First Flood: 1786-10-05Last Flood: 2011-09-09 Crest: 25.17 ft.Datum change: 1928-10-01Number of Floods: 48

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Height Above Flood Stage for Entire Period of Record
Height Above FSTotal OccurencePercent of Crest OccurrenceCumulative Total Flood OccurrencePercent of Floods above Listed Value
17 ft to 18 ft919.117 ft or above 47100.0
18 ft to 19 ft1123.418 ft or above 3880.9
19 ft to 20 ft714.919 ft or above 2757.4
20 ft to 21 ft714.920 ft or above 2042.6
21 ft to 22 ft24.321 ft or above 1327.7
22 ft to 23 ft24.322 ft or above 1123.4
23 ft to 24 ft12.123 ft or above 919.1
24 ft to 25 ft24.324 ft or above 817.0
25 ft to 26 ft36.425 ft or above 612.8
26 ft to 27 ft12.126 ft or above 36.4
27 ft to 28 ft00.027 ft or above 24.3
28 ft to 29 ft00.028 ft or above 24.3
29 ft to 30 ft12.129 ft or above 24.3
30 ft to 31 ft00.030 ft or above 12.1
31 ft to 32 ft00.031 ft or above 12.1
32 ft to 33 ft00.032 ft or above 12.1
33 ft to 34 ft12.133 ft or above 12.1
Height Above Flood Stage After Datum Change
Height Above FSTotal OccurencePercent of Crest OccurrenceCumulative Total Flood OccurrencePercent of Floods above Listed Value
17 ft to 18 ft620.017 ft or above 30100.0
18 ft to 19 ft826.718 ft or above 2480.0
19 ft to 20 ft413.319 ft or above 1653.3
20 ft to 21 ft413.320 ft or above 1240.0
21 ft to 22 ft26.721 ft or above 826.7
22 ft to 23 ft00.022 ft or above 620.0
23 ft to 24 ft13.323 ft or above 620.0
24 ft to 25 ft13.324 ft or above 516.7
25 ft to 26 ft26.725 ft or above 413.3
26 ft to 27 ft00.026 ft or above 26.7
27 ft to 28 ft00.027 ft or above 26.7
28 ft to 29 ft00.028 ft or above 26.7
29 ft to 30 ft13.329 ft or above 26.7
30 ft to 31 ft00.030 ft or above 13.3
31 ft to 32 ft00.031 ft or above 13.3
32 ft to 33 ft00.032 ft or above 13.3
33 ft to 34 ft13.333 ft or above 13.3





Codes and description

C1|Crest information looks unreliable and incomplete and not used in frequency calculations. Some of the floods are based on current flood stage and nearby gage information.
C2|Crest information looks reliable despite potential problems. This data was used in frequency calculations.
C3|Crest height estimated by the USGS.
C4|Crest height is from the National Weather Service.
C5|Crest height affected by backwater.
C6|Crest occurred at a previous flood stage that is lower than the current flood stage. The crests below the new flood stage are not used in flood frequency calculations.
C7|Crest from USGS yearly peak and/or date is different than the crest we provide. In many cases MARFC uses crest based on backwater or ice effects.
C8|Crest month or day of occurrence has been estimated by The Middle Atlantic River Forecast Center usually based on nearby gage information.
C9|Crest date (day) in the month is unknown.
F1|Flow is an estimate.
F2|Flow affected by regulation or diversion and in some cases to an unknown degree.
F3|Flow effected by snow-melt, ice jam or debris jam break up.
F4|Flow affected by dam failure.
F5|Flow - All or part of the record affected by urbanization, mining, agricultural changes, channelization or other factors.
G1|Gage height at a different site and/or datum.
G2|Gage is not an official USGS gage with crests provided by the NWS. Crest information looks unreliable and incomplete and not used in flood frequency calculations.
G3|Gage datum changed during this year.
none,No code; Good Data

Updated: 08:09 AM Feb 08, 2013