U.S. Geological Survey New Hampshire - Vermont Water Science Center
Peak River Stages, Discharges, and Approximate Recurrence Intervals
Provisional Data (subject to revision) for Floods of April 16-18, 2007
			Flood Peak					Previous Maximum in Record
Station Number	Station Name	Drainage Area	Stage	Discharge		Date	Recurrence Interval	Stage	Discharge	Year	Record
		sq.mi.	Feet	CFS	CFSM		years	Feet	CFS		Start Year
Piscataqua River Basin
01072800	Cocheco River near Rochester, NH	85.7	20.80	6,500	75.8	17-Apr	≥100*	18.86	5,550	2006	1995
01072870	Isinglass River near Dover, NH	74	22.25	6,400	86.5	17-Apr	≥100	19.37	4,370	2006	2002
01073000	Oyster River near Durham, NH	12.1	10.20	1,300	107.4	17-Apr	≥100	8.47	873	1996	1935
01073500	Lamprey River near Newmarket, NH	183	17.49	8,450	46.2	18-Apr	≥100	18.31	8,970	2006	1934
01073587	Exeter River at Haigh Road near Brentwood, NH	63.5	11.19	2,840	44.7	17-Apr	≥100	12.00	3,520	2006	1996
01073785	Winnicut River at Greenland near Portsmouth, NH	14.1	5.93	1,030	73.0	16-Apr	≥100	6.30	1,450	2006	2002
Merrimack River BasinRiver Basin
01078000	Smith River near Bristol, NH	85.8	8.65	2,770	32.3	17-Apr	2-10	16.09	8,100	1936	1918
01081000	Winnipesaukee River at Tilton, NH	471	7.61	3,550	7.5	17-Apr	10-50	8.68	4,580	1984	1937
01081500	Merrimack River at Franklin Junction, NH	1,507	13.62	17,300	11.5	17-Apr	10-50	36.40	83,000	1936	1903
01082000	Contoocook River at Peterborough, NH	68.1	7.21	4,110	60.9	16-Apr	≥100	6.13	3,210	2004	1945
01085000	Contoocook River near Henniker, NH	368	14.47	12,900	35.1	17-Apr	10-50	21.30	22,200	1938	1940
01086000	Warner River at Davisville, NH	146	11.42	6,910	47.3	17-Apr	100	12.35	8,640	2006	1939
01089100	Soucook River at Pembroke Rd near Concord, NH	81.9	13.37	3,730	45.5	17-Apr	10-50	14.92	5,110	2006	1988
01091500	Piscataquog River near Goffstown, NH	202	13.05	11,500	56.9	16-Apr	≥100	12.55	10,100	2006	1939
01092000	Merrimack River below Manchester, NH	3,092	16.79	59,700	19.3	17-Apr	50-100	35.19	150,000	1936	1937
01094000	Souhegan River at Merrimack, NH	171	12.72	10,600	62.0	17-Apr	50-100	16.20	16,900	1936	1909
010965852	Beaver Brook at North Pelham, NH	47.8	13.52	1,900	39.7	16-Apr	10-50	14.9	2,940	2006	1987
01100505	Spicket River at North Salem, NH	16.5	5.99	418	25.3	17-Apr	2-10	7.06	801	2006	2000
01100561	Spicket River near Methuen, MA	62.1	8.99	1,120	18.0	18-Apr	2-10	12.15	>2,260	2006	2000
	Stations with new record stage and discharge
*Floods having a 1 in 100 chance of being equalled or exceeded in any given year.
CFS	Cubic feet per second
CFSM	Cubic feet per second per square mile of drainage area
FEMA	Federal Emergency Management Agency
POR	Period of record is less than 10 years, recurrence interval not determined
Recurrence Interval = average time interval between occurrences of a hydrological event in years