The Waterways of Delaware
Lifeblood of a Region

from Pleistocene to Pencader
a populist discourse

By E. Lowell Jacobs, PE

Delaware is a remarkable area and exists because of unique geologic and natural resources, especially waterways, which greatly influenced the development of our human culture.

Although the earth is an estimated six billion years old, the Pleistocene era starting only two million years ago is when the general current configuration of the land masses was more or less stable, and the main current plant and animal species were developing.

In ancient times the geography of Delaware was enormously different. As recently as the last ice age a mere 10-20,000 years ago, the water level on our coast was believed to have been as much as 250 feet lower because of the amount of water bound up in ice; there would have been no ‘Chesapeake’ and ‘Delaware’ Bays, only drainage courses, and the shoreline would have been many, many miles offshore. Geologically, the upper portion of our state is characterized as rolling and somewhat rocky-‘Piedmont Plateau’- and the lower portion being flat and of sedimentary composition-‘Coastal Plain’- created by millennia of rising and falling sea levels with repeated cycles of depositions and erosions, with the dividing line between the two classifications being right thru our Pencader area, and may be the structure on which the Dayett Mills millrace is situated.

As the ice retreated northward and more moderate temperatures returned, the water levels rose and the bays formed and the current drainage features became established. Delaware, being a coastal land mass, developed a significantly abundant and varied watercourse system. Downstate we have the inland Bays of Assawoman, Indian River, and Rehoboth; also a series of interconnected inland natural and manmade waterways paralleling the coastline that we refer to as the Inland Waterway. A dominant feature is the Delaware River drainage basin comprising the lower Delaware Bay, the main body of the tidal Delaware River, and the upper Delaware which is tidal to Trenton and fresh for many more miles up into Pennsylvania, draining an area of approximately 15,000 square miles. Our neighbors to the immediate west-Maryland-acquired the even larger Chesapeake Bay system. These natural waterway systems developed an enormous variety and abundance of food and transportation opportunities. Early Native Americans-Indians-slowly exploring and migrating northward found the region to be very hospitable indeed. At some point several thousand years ago, they discovered our area and the unique resource of the Jasper deposits at Iron Hill which they could make tools and weapon points out of. Later the same area would be exploited by the incoming Europeans for iron ore mining. There are also many tributary rivers feeding the Delaware, almost all of which are tidal where they join the Delaware, but all used heavily for transportation and food harvesting in earlier times by both the Native Americans and the later Europeans.

As the area was being developed by the various European cultures, eventually a border dispute arose between Lord Baltimore of Maryland and William Penn of Pennsylvania about where the border between their territories was. This led to the famous Mason-Dixon survey which established the northern and eastern boundaries. Division of the enormous riches of the Bays probably led to Maryland keeping the Chesapeake Bay system and Pennsylvania acquiring the Delaware Bay system and half of the interlaying peninsula, which became known as the three lower counties of Pennsylvania, and allayed Pennsylvania’s fear of becoming landlocked with no ready access to the ocean, in an era when cross Atlantic commerce was still very prevalent.

Those three lower counties of Pennsylvania were blessed with a wealth of natural resources and developed thriving cultures based on the waterways including market hunting, commercial fishing, oystering, and commercial and recreational transport, to an extent unprecedented anywhere in the colonies, and supplemented by a thriving agriculture and business and commercial development, the residents therein developed an attitude that said ‘who needs those stuck-up Penn Pennsylvanians anyway, we don’t need them and we want to split off and be our own state and govern ourselves’, which eventually happened, forming the remarkable little state of Delaware, but it probably wouldn’t have happened without the driving force of the abundant riches of the waterways.

An enormous number of activities developed in the region based on the use of water. The attached list is probably not all inclusive, but it’s a good start. Most of Delaware’s industry would not have been possible without the abundance of water.

This list of three dozen things Delaware water is used for could easily be expanded. The major uses we’ll be discussing here are water for power (mechanical power to turn shafts and drive belts; ie the mills through water wheels or turbines); transportation, from the Native Americans through the natural rivers and the commercial canals like the C&D ; and food production, including commercial hunting, oystering, and fishing. There were many other uses, some more colorful than others, such as pirating-Blackbeard and other pirates apparently hung out in the downstate coastal areas on occasion- and slaving, both for transport bringing new ones in, the occasional use of the rivers and bays as part of the Underground Railroad runaway route, and partial transport back south after capture.

Apparently under the theory that if a little of something is good, a lot would be even better, the colonizing entrepreneurial Europeans started building supplemental canals and other water features right away largely to enhance commercial transport and industrial opportunities. There are reportedly 57 named canals in Delaware, the C&D being the best known and one of the worlds most successful ever, and some 30 named millponds, and quite possibly many more that are unnamed or forgotten. Two additional areas of significant manmade efforts would be the agricultural drainage improvement ditches largely downstate called ‘tax ditches’ and the mosquito control ditches mostly in the upstate marshes.

A major use of Delaware water was the generation of power through water powered mills. The Brandywine and Christina Rivers in our area here in northern Delaware had sufficient fall-change in elevation- and volume to turn waterwheels and later turbines to drive shafts to operate machinery or to turn stones to grind grain into flour and other products. Without the resource of the Brandywine Creek, the DuPont Powder Company might not have materialized and the face of Delaware and possibly the country could be different, as the DuPont gunpowder played a significant role in our military and political history. Many other major industries developed along the rivers due to the dependable water power resource. At various times through the nearly 300 years of water power, several hundred mills of various sorts were built throughout the State.

Locally, here in our very own Pencader area, we have a modest but significant stretch of the Christina River, with sufficient head and volume to successfully operate water powered mills. It should be mentioned that there were other types of mills located along the river banks that did not depend on water power. Most sawmills, and there was probably at least as many as there were grist mills, were manually operated with large one man or two man saws in saw pit configuration. Their locations in the floodplains may have been due to an availability of cheap land or the presence of a road or a co-owner of a grist mill or other economic factors, or even simple site cleanup by the waste materials being dumped in the nearby stream and carried away. The Shane Cider Mill comes to mind on Creek Road north of Newark, which sat on the bank of the White Clay Creek, but was powered not by water but by a Ford Model A engine and transmission and probably flushed its waste directly into the creek. Its location was probably a matter of the economies of the location, not the presence of water power. There could also be animal powered turnstile style mills for specialty products such as sorghum cane grinding, again not dependent upon water power. And while all our known mills were either stream flow operated directly or through ponds, tidal capture and release mills were known in other areas, and windmill operated mills were especially known in Europe but not here.

Along our Pencader section of the Christina River, a number of water powered mills (and others) are either known or suspected. The accompanying exhibit shows the most current speculation:

The Christina River just above Welsh Tract Road was the location of what was first the Abington Iron Works, circa 1720,a commercial iron ore smelting operation that never really got underway and failed economically, and the site later became the Fisher grist mill, the millers house of which remains on Art Lane today. On the south side of Interstate 95 about a quarter mile downstream on the Christina is the dam created first as a low dam for Lord Keith’s iron ore smelting furnace about 1720, which operated only about two years or so and failed economically because the product wasn’t very good. There would have been a blast furnace here and probably a drop- hammer mill to refine the product. There would have been a miller’s house somewhere nearby, and probably a collection of crudely built support buildings and services like a sunders store for supplies, blacksmith and carpentry shops etc. Very little documentation exists and except for the dam everything is long gone. The community even had a name: Keithsburg.

About the same time or a bit later, the modest flowage downstream at what was known as Purgatory Swamp was also damned just above where it joined the Christina. It had sufficient height to generate a useful amount of water power (volume of water may have been a limitation because this was not a continuously flowing stream), so chances are it was an independent business operation. No documentation exists, but we can speculate that this significant financial investment was done for a reason, and in all likelihood was for a mill site. In those days, if the dam could be incorporated into the public road system, public works funding from the government (British) might be possible, which appears to be what happened, although a separate bridge with road realignment was done many years later to the present configuration. The Americans and the British probably both marched across this dam in the 1777 battle.

The Cooch family directly across the Creek sometime after 1740 had a grist mill and possibly a sawmill. After the Battle of Cooches Bridge on Sept 3, 1777, the British enacted retribution by burning the Cooch mill(s), probably as much out of annoyance about the battle as much as a standard tactic of war, which disruption of business of the enemy is. Keith’s furnace had probably long since disappeared, and we don’t know what might have been present at the Purgatory Swamp location, but if anything was left, the British likely burned them too.

The war was over in a few more years, and in 1792, some serious reconstruction of the local milling industry occurred. A new mill site immediately downstream of what we now call Old Baltimore Pike was selected, and the millrace extended from the Christina , where the old low head dam was reconstructed and doubled in height to enable water to flow at grade down the new millrace, which it wouldn’t have at the old lower height, to the Purgatory Swamp pond and then on downstream to the new mill location. This gave the new mill a very nice water supply for potentially unlimited operation and sufficient volume for considerable power generation. No details are known except it was probably a grist mill. Curiously, we don’t know how they got the water over the road at the high elevation necessary so it could be dropped down onto probably a wooden overshot wheel. It could have been done in a suspended wooden viaduct over the road. There’s not a lot of vertical clearance, but the traffic on the road wouldn’t have been very tall anyway, so maybe that would work. The foundation of this mill was later incorporated into the present white barn structure you see there now, and the trickle of water you see leaving the barn area at the foot of the bluff is the old millrace that eventually reaches the Christina.

The evolving technology in the milling industry likely spurred the development 30 some years later to build a modern facility, so a new site was selected downstream and the present Cooch/Dayett mills constructed about 1822. The millrace was accordingly extended and the elevations were such that the flow could be passed through a culvert under Old Baltimore Pike, which is roughly the configuration you see today, although the present culvert would be a later replacement. There were apparently no other water based mills on the Christina on down to Route 72. One has to speculate that Silver Lake, however, was probably built as a mill pond, and we know Lum’s Pond was, and Beck’s Pond, but nothing else in our immediate area.

Our own Cooch/Dayett mills system was severely damaged by Hurricane Andrew in 1999 and underwent emergency stabilization and restoration activities, including restoration of the main dam in the Christina River, the Purgatory Swamp (or Secondary) dam downstream, and several associated millrace structures. Construction techniques not visible since the main dam was raised in 1792-the original was probably half the present height and built by Lord Keith for his short lived iron ore smelting furnace- were revealed by the storm damage. The main dam for example appears to have been constructed to shape by the use of trapezoidal timber templates, an open ‘space frame’ approach with templates about every 10-12 feet that the workers simply filled with miscellaneous fill in the middle and better material as it approached the frame shape, and large carefully placed armoring stone as the top course, all dry laid as this well preceded the availability of cement based concrete in this country. Some of the fill material may have been left over slag from Lord Keith’s failed earlier iron ore furnace operations. Likewise the upper millrace appears to have been stabilized to sustain higher erosive flows by a technique known as ‘puddling’, whereas alternating layers of smallish stone would be combined with layers of clay as a binder to increase the scour resistance over the native soil materials. Although there is no supporting documentation, this template technique could have also been used for construction of the new millrace, with the template being an inverted trapezoidal timber frame.

In order to work on the main dam in 2000, it was necessary to dewater the area, which was accomplished by the use of a steel and fabric cofferdam which diverted the entire flow of the Christina down the considerably smaller millrace, but with the addition of supplemental discharge pipes, was successfully accomplished. Most of the reconstruction was done with consideration for historical techniques and appearances, and has performed pretty well in the succeeding 10 years, with only one timber structure presently undergoing repair. The sediment filled Purgatory Swamp Pond is currently being prepared for funding for a sediment removal program that we hope will happen shortly. It would be a shame if a 260 year old pond were allowed to die when the benefits of restoration are so significant. As you may know, administrative management to develop public user programs for the present Cooch/Dayett Mills complex has recently been assigned to the Delaware Nature Center organization and the State is performing some modest repair and upgrade activities. Restoration to demonstration capability seems to be the long term goal, with full restoration requiring such a significant amount of funding that it doesn’t seem very immanent. It’s an uncertain future for the mill that served the community so well for so many years.

The era of dominance of our waterways in the development of our Delaware culture is largely behind us: electricity replaced water power; first the railroads and now the trucking industry replaced most water transport; and food production became structured land-based agriculture. It was, however, a remarkable 300 year period!

A modest bibliography to learn more:

“The District-a History of the Philadelphia District of the U.S.Army Corps of Engineers-1866-1971” by Frank E. Snyder and Brian H. Guss, 1973. Early water based engineering projects in our area. Probably long out of print but ask them anyway.

“A Guide to the History and Heritage of Pencader Hundred” by Judith (Judy) Pfeiffer and Robert C. (Bob) Barnes-24 known historically significant sites in the Pencader area. Available through the Pencader Museum. Excellent.

Port Penn Waterman’s Museum in Port Penn Delaware down Route 9.

Iron Hill Museum near Route 896 and Old Baltimore Pike near Newark.

Pencader Heritage Museum at Route 72 and Old Baltimore Pike near Newark.

Webpage Updated: FLR on: 2/22/2008