Introduction and Summary:

Introduction: This essay briefly describes the evolution of the New Hampshire drainage routes using the “thick ice sheet that melted fast” paradigm developed during the Missouri River drainage basin landform origins research project. Topographic map evidence from which this essay’s interpretations were made is not included here. Detailed topographic map evidence for the Missouri River drainage basin west of the Mississippi River used to develop the fundamentally new geomorphology paradigm is illustrated and discussed in the hundreds of published Missouri River drainage basin landforms origins research project essays (or research notes) on this website’s sidebar. Each essay illustrates and discusses detailed topographic map evidence for a specified Missouri River drainage basin drainage divide area. When completed the essay series will illustrate and describe evidence for all Missouri River drainage basin drainage divide areas.

The systematic headward erosion of present-day New Hampshire drainage basins carved the New Hampshire landscape we see today.  New Hampshire drainage basins were eroded headward by immense floods, probably resulting from rapid melting of a thick continental ice sheet. Flood water came from the northwest and to a lesser extent from the north and northeast and flowed on a topographic surface at least as high as the topographic surface that is today represented by the highest New Hampshire White Mountain erosion surfaces. How that original topographic surface related to sea level and has since been tectonically warped has not been determined.

Systematic headward erosion of five major drainage systems accounts for almost all New Hampshire erosional landscape features. To the west headward erosion of the Connecticut River drainage system systematically captured southeast-oriented flood water, beheading and often reversing southeast-oriented flood water routes to other New Hampshire drainage basins. The Merrimack drainage basin originally eroded headward from the Narragansett Bay area and from the developing Connecticut River Valley and was subsequently captured when a southwest-oriented flood flow route developed a direct outlet to the Atlantic and reversed flow direction so as to capture south-oriented floods carving the Merrimack River drainage basin. Southeast-oriented flood flow into the Merrimack River drainage basin was systematically beheaded and reversed by headward erosion of the Connecticut River Valley to the west. The Piscataqua-Salmon Falls River drainage basin eroded northwest into the Lake Winnipesauke area until headward erosion of the Merrimack River drainage basin beheaded and captured the southeast-oriented flood flow. Subsequent deposition of flood carried and other sediments blocked southeast-oriented drainage routes to create present-day lakes and to divert water from the northwest end of the drainage basin into the Merrimack River Valley. The Saco River drainage basin eroded headward into New Hampshire until headward erosion of the Connecticut River Valley and the Androscoggin River Valley beheaded and captured the southeast, south, and southwest-oriented flood flow going to the Saco River drainage basin. The Androscoggin River, upper stream from Upper Village, NH was initiated by floodwaters moving south to the Saco River drainage and was captured when floodwaters moving west and southwest to the Saco River drainage basin were beheaded, captured and reversed by headward erosion of the south-oriented Androscoggin River drainage in Maine.  That capture enabled the deep Androscoggin Valley and drainage basin to erode westward to Upper Village and northward into northern New Hampshire and the northwest corner of Maine.

 

Connecticut River Tributaries:

Ashuelot River: The Ashuelot River flows in a south, southwest, south, southwest, and northwest direction to join the Connecticut River near Hinsdale, NH. The turn from a southwest to northwest direction is located near Winchester, NH where the north-oriented Mirey Brook joins the Ashuelot River. Mirey Brook headwaters are linked by through valleys to south-oriented tributaries flowing to the west-oriented Millers River in Massachusetts. Just south of Keene, NH the north-flowing Ashuelot River Branch joins the southwest-flowing Ashuelot River and is also linked by through valleys to south-oriented tributaries flowing to the west-oriented Millers River. Further north at the turn from southwest-oriented to south-oriented the Ashuelot River is joined by the south-oriented Thompson Brook which is linked by through valleys to the north-oriented Camp Brook flowing to the west oriented Cold River and to a northwest-oriented Connecticut River tributary (this is a barbed tributary flowing north to join a south-oriented river). The Ashuelot River headwaters are linked by through valleys with north-oriented Cold River headwaters and tributaries. The above evidence suggests the Ashuelot River drainage network eroded headward across a region to capture south-oriented flood flow moving to the Millers River drainage basin to the south. Headward erosion of the Ashuelot River drainage system captured that south-oriented flood flow and diverted it to the Connecticut River Valley. Subsequently, headward erosion of the Cold River drainage network to the north beheaded the south-oriented flood flow into the Ashuelot River drainage basin, ended erosion and development of the Ashuelot River drainage network, and diverted the flood flow into what must have been the evolving Connecticut River Valley.

Cold River: The Cold River starts near Crescent Lake in an east to west through valley and flows west before turning south, then west, and finally southwest to join the Connecticut River opposite of Bellows Falls, VT. The east to west through valley at Crescent Lake is drained by the west and northwest oriented Little Sugar River flowing to the south-oriented Connecticut River as a barbed tributary. The south-oriented Cold River segment is linked by a through valley to north-oriented Spring Brook and South Branch flowing to the west-oriented Sugar River that joins the Connecticut near Claremont, NH. South-flowing tributaries to the west and southwest-oriented Cold River segments are linked by through valleys to north and northwest-oriented drainage to Little Sugar River and or to other barbed Connecticut River tributaries. North-oriented Cold River tributaries are linked by through valleys to south-oriented Ashuelot River tributaries. Evidence indicates the Cold River drainage network eroded headward across south-oriented flood water moving to the Ashuelot River drainage basin and that the south-oriented flood water into the Cold River drainage basin was beheaded and diverted west to the Connecticut River Valley by headward erosion of the Little Sugar and Sugar River drainage networks.

Little Sugar River: The Little Sugar River flows south from the Marshall Pond area, then west, and finally northwest to join the Connecticut River as a barbed tributary near North Charlestown, NH. The west-oriented Little Sugar River segment is linked by the east to west oriented through valley at Crescent Lake with the east-oriented Cold River headwaters. A north-oriented Sugar River tributary is linked to south-oriented Chase Brook, flowing to the Little Sugar River, by a through valley. North-oriented Little Sugar River tributaries are linked by high-level through valleys to south-oriented Cold River tributaries. Evidence suggests that south-oriented flood water moved through the Little Sugar River drainage basin to the Cold River drainage basin until headward erosion of the Little Sugar River drainage network captured that south-oriented flow. Development of the Little Sugar River drainage network ended when headward erosion of the Sugar River drainage network subsequently captured the south-oriented flood flow.

Sugar River: The Sugar River is formed north of Newport, NH at the confluence of the south-oriented North Branch and the north-oriented South Branch and flows southwest, west, and finally northwest to join the Connecticut as a barbed tributary near Claremont, NH. The north oriented South Branch is linked by through valleys to south-oriented Ashuelot River headwaters. The south-oriented North Branch is linked by through valleys to northwest-oriented drainage flowing to the west-oriented Mascoma River. The south-oriented North Branch and the southwest-oriented Sugar River segment are linked by through valleys to northwest-oriented drainages that eventually reach the south-oriented Connecticut River (as barbed tributaries). For example, southeast-oriented Swamp Brook is linked by a high-level through valley to northwest-oriented Newton Brook-Blood Brook and southeast-oriented Beaver Brook is linked by a high-level through valley to the northwest-oriented Blow-me-down Brook. Note: northwest-oriented Blow-me-down Brook flows in what is an anastomosing complex of through valleys paralleling the Connecticut River Valley that can only be explained by a south-oriented flood that was systematically captured by headward erosion of the present-day drainage network.  On the larger scale the Sugar River drainage network eroded headward to capture south-oriented flood water moving to the Little Sugar River, Cold River, and Ashuelot River drainage basins and Sugar River drainage network development ended as the Mascoma River drainage network beheaded and diverted the south-oriented flood flow west to the Connecticut River Valley.

Mascoma River: The Mascoma River begins south of Smarts Mountain and flows south to where it joins the west-oriented Indian River to flow west to Mascoma Lake where it is joined by the northwest-oriented Knox River and then flows west to join the south-oriented Connecticut River near West Lebanon, NH. South-oriented Mascoma River tributaries are linked by through valleys to west-oriented Mink Brook, which flows to the Connecticut at Hanover, NH. The south-oriented Mascoma River segment is linked by through valleys to west-oriented Grant Brook. Pressey Brook flows south from a through valley linked to northwest-oriented Hewes Brook drainage to join the west-oriented Mascoma River segment. South-oriented Mascoma Lake tributaries flow from a through valley, which is drained north-oriented drainage to the west-oriented Mink Brook. The northwest-oriented Great Brook, which flows to the Mascoma River at Lebanon, NH, is linked by a high-level through valley to south-oriented Sugar River drainage. Stony Brook flows northwest from a through valley linked with south-oriented drainage to Sugar River.  Evidence suggests the Mascoma River drainage network eroded headward across south and southeast-oriented flood flow moving into the Sugar River drainage basin and captured that flow. South and southwest-oriented flood flow into the Mascoma River drainage basin was subsequently captured and diverted by headward erosion of the Connecticut River – Mink Brook valley.

Knox River: The Knox River flows northwest into Mascoma Lake and is linked by through valleys to south-oriented drainage to the Sugar River. The northwest-oriented Knox River Valley was originally eroded by southeast-oriented flood water moving to the Sugar River drainage basin and was reversed when headward erosion of the Connecticut River-Mascoma River Valley captured that flood flow.

Indian River: The Indian River flows south-southwest and then west to join the Mascoma and then flow to Mascoma Lake. Indian River headwaters flow from a through valley also used a south-southwest-oriented Cockermouth River valley segment. The Cockermouth River turns southeast from that through valley to join the south-oriented Pemigewasset River. The through valley extends further north and is also used by a south-oriented Baker River segment. The south-oriented Baker River also turns southeast to flow to the south-oriented Pemigewasset River. Where the Indian River turns from south-southwest oriented to west-oriented a southeast-oriented through valley drained by the Smith River goes to the south-oriented Pemigewasset River. Evidence suggests the through valleys were carved by an anastomosing complex south-oriented floodwaters that were being simultaneously captured by headward erosion of the deep Pemigewasset River drainage network to the east and the deep Connecticut River drainage network to the west.

Ammonoosuc River:  The Ammonoosuc River flows west from Mount Washington, then northwest, southwest and finally west to join the Connecticut River at Woodville, NH (opposite Wells River, VT). The headwaters area is linked by high level through valleys to northwest-oriented Israel River tributaries. Between Twin Mountain and Alderbrook, the west and northwest-oriented Ammonoosuc River is linked by through valleys to the northwest-oriented Johns River. At Littleton, NH a major northwest-oriented through valley links the southwest-oriented Connecticut River Valley with the southwest-oriented Ammonoosuc River Valley. South and southeast-oriented tributaries to the southwest-oriented Ammonoosuc Valley are also linked by high-level through valleys to the southwest-oriented Connecticut River. The northwest-oriented Wild Ammonoosuc River, which joins the southwest-oriented Ammonoosuc Valley where it turns west, is linked by a through valley at Kinsman Notch to the southeast-oriented Lost River flowing to the south-oriented Pemigewasset River. North-flowing Whitcher and Tunnell Brooks flowing to the northwest-oriented Wild Ammonoosuc River are linked by deep through valleys to south-oriented drainage to northwest-oriented Oliverian Brook flowing to the south-oriented Connecticut River. Oliverian Brook flows northwest in a through valley that is drained to the southeast to the south and southeast-oriented Baker River flowing to the south-oriented Pemigewasset River. At Crawford Notch the Ammonoosuc River is linked to the southeast-oriented Saco River.  The north-oriented Zeeland River, west of Crawford Notch, is linked at Zeeland Notch to south-oriented drainage to the south-oriented Pemigewasset River. The Gale River, a northwest-oriented Ammonoosuc tributary, is linked at Franconia Notch to headwaters of the south-oriented Pemigewasset River.  The evidence demonstrates that massive amounts of southeast oriented flood water moved across the Ammonoosuc River drainage basin and present-day White Mountains to the eroding Pemigewasset and Saco River drainage networks and was captured by headward erosion of the deep Connecticut River-Ammonoosuc River Valley system. Present-day northwest oriented tributaries developed as reversals of flow on valleys that had been initiated by the southeast-oriented floodwaters.  Franconia Notch, Zeeland Notch, Kinsman Notch, Crawford Notch and other spectacular through valleys across the White Mountains provide evidence of the magnitude and volume of the southeast oriented flood water and also of the degree to which that flood water eroded the surrounding landscape.

Johns River: Johns River flows in a northwest direction in a broad valley to join the southwest-oriented Connecticut River near South Lunenburg, VT. The northwest-oriented Johns River Valley is linked by a broad through valley to the west-oriented Ammonoosuc River Valley and to valleys of northwest-oriented Ammonoosuc River tributaries. This linkage indicates the Johns River Valley was probably initiated by southeast-oriented floodwater that went to the developing Saco River drainage basin through Crawford Notch and to the developing Pemigewasset River drainage basin through Zeeland, Franconia, and other notches. Headward erosion of the Connecticut-Ammonoosuc River Valley first captured that southeast-oriented flood flow causing southeast-oriented flow through the Johns River Valley to turn west and southwest. Continued headward erosion of the Connecticut River Valley then beheaded the southeast-oriented flow causing it to reverse to create the northwest-oriented Johns River.

Israel River: The Israel River flows from Mount Washington in a northwest direction to join the southwest-oriented Connecticut River. The northwest-oriented Israel River is linked by a deep through valley at Bowman to the east-oriented Moose River flowing to the south and east-oriented Androscoggin River west of Gorham, NH. The Israel River is linked by through valleys with the parallel northwest-oriented Johns River and further east, northwest oriented Israel River tributaries are linked by through valleys to south-oriented Ammonoosuc River tributaries. For example, the northwest-oriented South Branch Israel River is linked at Jefferson Notch with southwest-oriented Jefferson Brook flowing to the west-oriented Ammonoosuc River. The southwest-oriented Stag Hollow Brook, flowing to the northwest-oriented Israel River is linked to north-oriented Upper Ammonoosuc River headwaters. The Upper Ammonoosuc River turns west to join the Connecticut River at Groveton, NH. Like the Johns River Valley the northwest-oriented Israel River Valley was initiated by southeast-oriented flood water moving across the region to the developing Pemigewasset, Saco, and Androscoggin drainage networks and was reversed when the deep Connecticut River Valley eroded headward to capture the southeast-oriented flood flow.

Upper Ammonoosuc River: The Upper Ammonoosuc River flows north and then west to join the Connecticut River near Groveton, NH. Upper Ammonoosuc River headwaters are linked by a through to southwest-oriented Stag Hollow Brook and the northwest-oriented Israel River and by a high-level through valleys (e.g. Carlton Notch and Hunters Pass) to the east-oriented Moose River and east and southeast-oriented Androscoggin River. The northwest-oriented North Branch Upper Ammonoosuc River is linked to the southeast-oriented Dead River flowing to the south and southeast-oriented Androscoggin River. A south-oriented Upper Ammonoosuc River tributary, Phillips Brook, is linked at Kelsey Notch to northwest-oriented drainage to the west-oriented Mohawk River and to east-oriented West Branch Clear Stream flowing southeast to the south and southeast-oriented Androscoggin River. A south-flowing Upper Ammonoosuc tributary, Nash Stream, is linked by through valleys to northwest-oriented Simms Stream flowing to the south-oriented Connecticut River. The Upper Ammonoosuc River drainage network valleys were initiated by southeast-oriented flood flow moving across the region that was systematically captured and reversed by headward erosion of the deep Connecticut River-Upper Ammonoosuc River valley network.

Mohawk River: The Mohawk River flows in a west-northwest direction to join the south-oriented Connecticut River near Colebrook, NH. A deep through valley at Dixville Notch links the west-northwest-oriented Mohawk River with southeast-oriented Clear Stream, which flows to the south and southeast-oriented Androscoggin River. The south-southwest oriented North Branch Mohawk River, which joins the Mohawk River near Colebrook, is linked to north-northwest-oriented Bishop Brook flowing to the Connecticut near Beecher Falls. The south-southeast-oriented West Branch Mohawk River is linked by through valley to the deep northwest-oriented Cedar Brook-Bishop Brook Valley. The Mohawk River drainage network valleys were initiated by southeast-oriented flood flow moving across the region to the developing Androscoggin drainage network. That southeast-oriented flow was captured and reversed by headward erosion of the deep Connecticut River-Mohawk River Valley network and regional relief indicates the amount of erosion that took place.

Halls Stream: Halls Stream flows south-southeast and then south-southwest to join the Connecticut River at Beecher Falls. Tributaries come from the northwest in Quebec and flow southeast and are linked to northwest oriented tributaries flowing eventually to the northwest-oriented Saint Francis River and the northeast-orient Saint Lawrence River.  The deep Halls Stream valley eroded headward across southeast-oriented flood water that was subsequently captured by the northwest-oriented Saint Francis River, which flows to the northeast-oriented Saint Lawrence River.

Indian Stream: Indian Stream flows in a south-southwest direction to join the southwest-oriented Connecticut River segment upstream from Beecher Falls. Southeast oriented tributaries are linked by high-level through valleys to the parallel Halls Stream to the northwest and further north to northwest-oriented drainage to the northwest-oriented Eaton River flowing to the southwest-northwest-oriented Saint Francis River. Northwest and west-oriented Indian Stream tributaries are linked by high-level through valleys to southeast-oriented drainage to the south-southwest-oriented Perry Stream to the southeast. The Indian Stream Valley eroded headward across a southeast-oriented flood and beheaded flow moving to the parallel Perry Stream drainage basin and headward erosion of the parallel Halls stream Valley beheaded southeast flow into the Indian Stream drainage basin.

Perry Stream:  Perry Stream flows south-southwest to join the Connecticut River near Pittsburg, NH. Headwaters are linked to the northwest-oriented Middle Branch Indian Stream headwaters. Southeast-oriented Perry Stream tributaries are linked by high-level through valleys to northwest and west-oriented Indian Stream tributaries. High-level through valleys also indicate that Perry Stream captured southeast-oriented flood flow to the parallel south and southwest-oriented Connecticut River Valley to the southeast. Southeast-oriented flood flow into the Perry Stream drainage basin was captured by headward erosion of the parallel deep Indian Stream Valley to the northwest.

Connecticut River Headwaters: The Connecticut River headwaters appear to have eroded headward across southeast-oriented flood flow to the Dead Diamond and Diamond River drainage basins, which flow to the south-southwest-oriented Magolloway River flowing to the south and southeast-oriented Androscoggin River. Headward erosion of the deep Connecticut River headwaters valley captured south and southeast-oriented flood flow that had been eroding the Androscoggin-Magolloway-Diamond and Dead Diamond drainage network valleys. Southeast flow to the Connecticut River headwaters valleys was captured in sequence by headward erosion of the parallel Perry Stream, Indian Stream, and Halls Stream valleys. The Connecticut River headwaters valley is also linked by a high-level through valley to the north-oriented Dutton River, which flows to the north-northwest-oriented Au Saumon River and the southwest-northwest-oriented Saint Francis River. Flood water apparently came south along the Dutton River alignment and was captured and reversed as headward erosion of the Saint Francis River drainage network occurred.

Merrimack River and Tributaries

Shawsheen River (in MA): The Shawsheen River flows north-northeast and north to join the northeast-oriented Merrimack River at Lawrence, MA. The headwaters are linked to south-oriented drainage to the Charles River and Boston Bay and are aligned with north-oriented Charles River segments west and southwest of Boston. Shawsheen drainage route was initiated by south-oriented flood water that was captured, beheaded, and reversed by headward erosion of the deep northeast-oriented Merrimack River Valley. That northeast-oriented Merrimack River Valley segment probably began as a southwest-oriented flood flow route, but was captured and reversed when floodwaters spilled directly over into the Atlantic Ocean creating a more direct and shorter flow route. Once reversed the northeast-oriented Merrimack Valley quickly eroded headward to capture the south-oriented Merrimack River segment just west of Lowell, MA.

Concord River (in MA): The Concord River is formed by the confluence of the east and north-oriented Sudbury River and the northeast-oriented Assaber River at Concord, MA. From its origin the Concord River flows to join the northeast-oriented Merrimack River at Lowell, MA, just east of where the Merrimack turns from being a south-oriented river to become a northeast-oriented river.  The Concord River flows north on the same alignment as north-oriented Charles River segment uses further to the south and is linked to the south-oriented Mill River and Blackstone River both eventually flowing to Narragansett Bay. The Concord River drainage route was initiated by south-oriented floodwaters moving to Narragansett Bay and the floodwaters were captured, causing a reversal of flow, when the deep northeast-oriented Merrimack River Valley eroded headward.

Nashua River: The Nashua River flows in a north-northeast direction from the Wachusett Reservoir area to join the south-oriented Merrimack River at Nashua, NH. The north-oriented Nashua River is linked by through valleys in the Worcester area to the south-oriented Blackstone River flowing to Narragansett Bay. The North Nashua River flows south and southeast to join the north-northeast-oriented Nashua River. South-oriented North Nashua River headwaters, north of Fitchburg, are linked to the northeast and east-oriented Souhegan River flowing to the south-oriented Merrimack River at Merrimack, NH. The Nashua River drainage route was initiated by south-oriented floodwaters flowing from the Merrimack drainage basin to Narragansett Bay. Headward erosion of the deep Merrimack River Valley beheaded and reversed the south-oriented flood flow along the Nashua River route and then subsequently beheaded and reversed flow along the Souhegan River route to create the present-day Nashua River drainage network.

Souhegan River: The Souhegan River flows in a northeast and east direction to join the south-oriented Merrimack River at Merrimack, NH. Southeast-oriented tributaries link the eastern Souhegan Valley with northwest-oriented South Branch Piscataquog River and the western Souhegan Valley to northwest-oriented Contoocook River tributaries west of the Wapack Range. North-oriented Souhegan River tributaries are linked to south-oriented North Nashua River headwaters. The Souhegan valley originated as part of a south-oriented anastomosing channel complex that was systematically beheaded and reversed as the south-oriented flood flow was captured and diverted to flow through the Merrimack River Valley.

Piscataquog River: The Piscataquog River flows in a southeast direction to join the south-oriented Merrimack River at Manchester, NH. To the northwest, the Piscataquog River Valley is linked to the northeast-oriented Contoocook River Valley. Southeast-oriented Piscataquog River tributaries are also linked to northwest-oriented Contoocook River tributaries. The south Branch Piscataquog River flows southeast and then northeast to join the southeast-oriented Piscataquog River. South Branch headwaters are linked to the north and northeast-oriented Contoocook River. The Piscataquog River drainage network was eroded headward to capture, and in some cases behead and reverse, south and southeast-oriented flood water. South and southeast-oriented flood flow into the Piscataquog drainage basin was captured, beheaded, and reversed when the Contoocook drainage network was beheaded and reversed by headward erosion of the deep Merrimack River Valley.

Contoocook River: The Contoocook River flows north-northeast and northeast from just west of the Wapack Range to join the south-oriented Merrimack River at Penacook, NH. Headwaters are linked with south-oriented headwaters of the west-oriented Millers River flowing to the south-oriented Connecticut River. Continuing south on the headwaters alignment are headwaters of the south-oriented Burntshirt River that flows to the southwest-oriented Ware River and west-oriented Chicopee River that empties into the Connecticut River at Chicopee, MA. A through valley extending east from the Keene, NH area probably provided a link for south-oriented flood flow to move from the Contoocook River drainage basin to the south and southwest-oriented Ashuelot River drainage basin to the west. Perhaps more prominent are the major southeast-oriented Contoocook River tributaries coming from the northwest such as the Warner River and the Blackwater River and the complex of trough valleys linking all tributaries with tributaries of adjacent drainage basins. These linkages and through valleys suggest flood water moved southeast from the Sugar River drainage basin through a southeast and south-oriented anastomosing channel complex that was systematically captured and reversed to create the present-day Contoocook drainage network, cutting off flood flow to the Piscataquog drainage basin to the southeast and with flow beheaded by Connecticut River Valley headward erosion to the west.

Pemigewasset River: The Pemigewasset River is in reality the northern continuation of the Merrimack River with the name changing where the southwest and west-oriented Winnipesauke River and the Pemigewasset River join at Franklin, NH. The Pemigewasset begins at Franconia Notch in the White Mountains and flows in a generally south direction to Franklin where the name changes to the Merrimack River.

Smith River: The Smith River flows southeast and northeast to join the south-oriented Pemigewasset River at South Bristol, NH. The Smith River is linked by a deep northwest to southeast oriented through valley to the west-oriented Indian River-Mascoma River flowing to the South-oriented Connecticut River. The Smith River Valley was eroded by floodwaters that came from the northwest and west and captured by headward erosion of the Connecticut River to reverse flow on the Mascoma-Indian River route. The southeast-oriented Smith River segment uses the same alignment as the southeast-oriented Blackwater River flowing to the Contoocook River to the southeast. Southeast-oriented flood flow through the Smith River drainage basin to the Blackwater-Contoocook drainage basin was captured by headward erosion of the deep Merrimack-Pemigewasset-Smith River Valley.

Newfound-Cockermouth River: The Cockermouth River flows in a southeast direction to Newfound Lake and the Newfound River flows south from the Lake to join the south-oriented Pemigewasset River.  The Cockermouth River is linked to the north-oriented South Branch Baker River. Baker River flows southeast from its confluence with its north-oriented South Branch and joins the Pemigewasset River at Plymouth, NH. A north to south through valley connects the Baker River Valley at West Plymouth with Newfound Lake and the south-oriented Newfound River. The Newfound-Cockermouth River drainage network was eroded by floodwater that came from the north and northwest and that was captured, beheaded, and reversed by Pemigewasset River-Baker River headward erosion.

Baker River: Baker River flows south from the White Mountains and then southeast to join the Pemigewasset River at Plymouth, NH. A deep through valley links the south-oriented Baker River with the northwest-oriented Oliverian Brook flowing to the south-oriented Connecticut River near Haverhill, NH. The Baker River Valley is also linked by deep through valleys to the northwest-oriented Wild Ammonoosuc River, flowing to the southwest-oriented Ammonoosuc River and south-oriented Connecticut River. The Baker River drainage network was eroded by massive floods that came from the north and northwest and that were beheaded and captured by headward erosion of the deep Connecticut – Ammonoosuc River Valley network.

Pemigewasset River headwaters: The Pemigewasset River headwaters at Franconia Notch and southeast-oriented tributaries are linked by deep through valleys to northwest-oriented Ammonoosuc River tributaries. East Branch Pemigewasset River flows southwest through the White Mountains and its south-oriented tributaries are linked to north-oriented Ammonoosuc River tributaries. Northwest and north-oriented East Branch tributaries are linked by high level through valleys to east-oriented Saco River tributaries. Pemigewasset River headwaters evidence indicates the region was deeply eroded by massive floodwaters from the north and northwest that were beheaded and captured by headward erosion of the deep Connecticut and Ammonoosuc River Valleys.

Mad River: The Mad River begins at Mad River Notch and flows south and southwest to join the south-oriented Pemigewasset River near Compton Station, NH. At Mad River Notch the south-oriented Mad River is linked to northwest-oriented Hancock Branch of the Pemigewasset River East Branch. The southeast-oriented West Branch Mad River is linked to west, southwest and west-oriented Eastman Brook, which flows to the south-oriented Pemigewasset River. Northwest-oriented Mad River tributaries are linked by high-level through valleys across the Sandwich Range with southeast-oriented drainage to the Bearcamp-Ossipee-Saco River system. Sandwich Notch near Hall Ponds links a northwest-oriented Mad River tributary with southeast-oriented drainage to the west-oriented Beebe River. The deep Mad River drainage network was eroded headward into the mountains by south and southeast-oriented flood flow that was beheaded and captured by Pemigewasset River headward erosion. The flood flow that initiated the valley cutting must have moved on a topographic surface equivalent to or higher than the surface represented by present-day mountain crests.

Beebe River: The Beebe River flows west and southwest to reach the Pemigewasset River at Beebe River, NH. Beebe River headwaters are linked to southeast-oriented drainage to the southeast-oriented Bearcamp-Ossipee-Saco River system. A southeast oriented Beebe River tributary is linked at Sandwich Notch to a northwest-oriented Mad River tributary. Northwest-oriented Ryan Branch of the Beebe River is linked to south-oriented Owl Brook. The Ryan Branch-Owl Brook through valley parallels the Pemigewasset River with Mount Prospect standing between the two deep valleys. This situation of through valleys paralleling the Pemigewasset River is repeated at several other locations and suggests that Pemigewasset River headward erosion was along an anastomosing complex of south-oriented channels, with the present Pemigewasset River route representing the channel that was most deeply eroded. The deep Beebe River Valley was eroded headward across southeast-oriented flood flow that had to be moving on a topographic surface at least equivalent to that of the present-day Sandwich Range to enter the present-day Bearcamp-Ossipee-Saco River drainage basin. Southeast-oriented flow into the Beebe River drainage basin was beheaded and captured by headward erosion of the deep Pemigewasset River- Mad River valley system.

Winnipesauke River: The Winnipesauke River flows south and southwest from Lake Winnipesauke through several smaller lake basins and then west to join the Pemigewasset River at Franklin, NH, where the combined rivers form the south-oriented Merrimack River.

Through valleys to the southeast link the Winnipesauke River drainage basin to the southeast-oriented Piscataqua River drainage basin. To the north the Winnipesauke drainage basin is linked by a major through valley to southeast-oriented headwaters of the Bearcamp-Ossipee-Saco River system. To the northwest through valleys link the Winnipesauke drainage basin with the west-oriented Squam Lake drainage basin and the west-oriented Beebe River drainage further to the north. The Winnipesauke River drainage basin was apparently eroded headward by southeast-oriented floodwaters moving to the southeast-oriented Piscataqua River drainage system. The southeast-oriented drainage network was subsequently disrupted by the deposition of sediments (perhaps as flood flow directions or other conditions changed) that blocked the valleys to form lakes and caused overflow to the west to the deep Merrimack-Pemigewasset River Valley.

Soucook River: The Soucook River flows south to join the south-oriented Merrimack River at Concord, NH. Through valleys to north and northwest-oriented Winnipesauke River tributaries link the south-oriented Soucook River drainage basin with the west-oriented Winnipesauke River Valley. The Soucook River drainage network eroded headward until the south-oriented flood flow into the Soucook River drainage basin was captured by headward erosion of the deep Merrimack-Winnipesauke River Valley.

Suncook River: The Suncook River flows in a south-southwest direction to join the Merrimack River at Suncook, NH. Southeast-oriented Suncook River tributaries are linked to northwest and north-oriented Soucook River tributaries. Northwest and west-oriented Suncook River tributaries are linked to southeast and east-oriented drainage to the Piscataqua River. The Suncook River drainage network eroded headward to capture and behead southeast-oriented flood flow moving to the Piscataqua River system. Subsequently, headward erosion of the Merrimack River-Soucook River drainage network beheaded and captured southeast-oriented flood flow moving into the Suncook River drainage basin.

Saco River

Saco River: The Saco River flows south, east, south, and east into Maine from Crawford Notch. At Crawford Notch the Saco River is linked to northwest oriented drainage to the west and southwest-oriented Ammonoosuc River flowing to the south-oriented Connecticut River. A major Saco River tributary is the Ellis River that flows south from Pinkham Notch to join the Saco River where the Saco turns from east-oriented to south oriented. At Pinkham Notch the Ellis River is linked to the north-oriented Peabody River flowing to the east and northeast-oriented Androscoggin River at Gorham, NH. A major Ellis River tributary flows south-southwest from Perkins Notch where it is linked with the northeast-oriented Wild River flowing to the east and northeast-oriented Androscoggin River in Maine. The deep Saco River drainage system was eroded headward into the White Mountains to capture floodwaters that were converging on the area from the northwest and from the northeast. Flood flow from the northwest was captured, beheaded and reversed by headward erosion of the deep south-oriented Connecticut River Valley and the southwest and west oriented Ammonoosuc River Valley. Flood flow from the northeast was beheaded, captured and reversed by headward erosion of the south-oriented Androscoggin River Valley in Maine to create the east and northeast-oriented Androscoggin River Valley that crosses the New Hampshire-Maine border and the northeast-oriented Wild River Valley. Headward erosion of the reversed (now east-oriented) Androscoggin River Valley subsequently beheaded and reversed south-oriented flood flow from the upper Androscoggin River drainage network through Pinkham Notch to the Saco River drainage network and created the north-oriented Peabody River drainage basin.

Swift River: The Swift River is an east-oriented Saco River tributary that joins the Saco River where it turns east to flow into Maine. South-oriented Saco River tributaries are linked by deep through valleys to north-oriented tributaries flowing to an east-oriented Saco River Valley segment that parallels the Swift River to the north. East-oriented Swift River tributaries and headwaters are linked by through valleys to northwest-oriented tributaries to the southwest-oriented East Branch Pemigewasset River. The Swift River drainage basin was eroded by southeast and south-oriented floodwaters that were captured by headward erosion of the deep Swift River Valley.

Bearcamp-Ossipee River: The Bearcamp-Ossipee River flows east-southeast and joins the Saco River in Maine. North to south oriented through valleys link the south-oriented Saco River segment to the north with the Bearcamp-Ossipee River Valley and in the west extend south to the Winnipesauke River basin and in the east to the Pine River-Salmon Falls River-Piscataqua River drainage basin. The Bearcamp-Ossipee River drainage basin was formed by headward erosion across south oriented flood water from the Saco River drainage basin that was beheaded and captured by headward erosion of the Saco River. Headward erosion of the Bearcamp-Ossipee River drainage basin captured south and southeast-oriented flood flow moving to the Winnipesauke River drainage basin and to the Pine River-Salmon Falls River-Piscataqua River drainage basin.

Androscoggin River and tributaries

Androscoggin River: The Androscoggin River flows south from Errol, NH where it is formed at the confluence of the Magalloway River and Clear Stream. At the confluence of the Moose River the Androscoggin River makes a sharp turn to flow east and northeast into Maine and then south to the Atlantic Ocean.

Magalloway River: The Magalloway River flows south from near the Quebec border to its confluence with Clear Stream at Errol, NH where the Androscoggin River begins. The headwaters area is very close to the Connecticut River headwaters area and through valleys link the Magalloway with northwest-oriented and northeast-oriented Quebec drainage routes, suggesting that floodwaters that eroded the upper Magalloway Valley may have come from both directions. Further south major Magalloway tributaries flow southeast and include the Dead Diamond River and the Diamond and their headwaters are linked by through valleys to northwest-oriented tributaries to the southwest-oriented Connecticut River headwaters. To the southeast, in Maine, are various lake basins and through valleys southeast of those lake basins link the Magalloway River drainage basin with southeast-oriented tributaries flowing to the east and northeast-oriented Androscoggin River in Maine. Included among those southeast-oriented Androscoggin River tributaries are the Bear River, Ellis River, and Swift River. Overall the Magalloway River Valley eroded headward to capture and behead southeast-oriented flood flow moving to the east and northeast-oriented Androscoggin River in Maine. Southeast-oriented flood flow to the Magalloway River drainage was captured and beheaded by headward erosion of the Connecticut River and headwaters drainage system.

Clear Stream: Clear Stream flows southeast from Dixville Notch to the Androscoggin River at Errol, NH. At Dixville Notch Clear Stream is linked with the west-oriented Mohawk River flowing to the south-oriented Connecticut River. The Clear Stream drainage basin was eroded by southeast-oriented flood water that was captured and beheaded by headward erosion of the Connecticut River drainage basin that created the west-oriented Mohawk River.

Dead River: The Dead River flows southeast to join the south-oriented Androscoggin River at Berlin, NH. The Dead River is linked to the northwest-oriented North Branch flowing to the northwest and west-oriented Upper Ammonoosuc River and the south-oriented Connecticut River. The Dead River drainage basin was eroded by southeast-oriented flood water that was captured and beheaded by headward erosion of the Connecticut River drainage basin that created the northwest and west-oriented Upper Ammonoosuc River.

Moose River: The Moose River flows east and northeast to join the east oriented Androscoggin River at Upper Village, NH. The Moose River is linked to the northwest oriented Israel River and the southwest and south-oriented Connecticut River. The Moose River drainage basin was eroded by southeast-oriented flood water that was captured and beheaded by headward erosion of the Connecticut River drainage basin that created the northwest -oriented Israel River.

Peabody River: The Peabody River flows north-northeast from Pinkham Notch to join the east-oriented Androscoggin River at Gorham, NH. The Peabody River is linked to the south-oriented Ellis River flowing to the south and east-oriented Saco River. The Peabody River drainage basin was eroded by south-oriented flood water that was captured and beheaded by headward erosion of the Androscoggin River drainage basin that created the north-oriented Peabody River.

Wild River: The Wild River flows northeast from Perkins Notch to join the east and northeast-oriented Androscoggin River at Gilead, ME. The Wild River is linked to south, east and southeast-oriented Saco River. The Wild River drainage basin was eroded by southwest-oriented flood water that was captured and beheaded by headward erosion of the south-oriented Androscoggin River drainage basin that created the east and northeast-oriented Androscoggin River segment (that eroded west to capture the south-oriented Androscoggin River segment in New Hampshire) and the northeast-oriented Wild River.