Issues With River Systems in the United States

 by Edward Ulrich, updated September 29, 2022


This article details issues with the river systems in the United States, and it details a theoretical concept of harvesting river water for irrigating cropland.

[Note: September 29, 2022— The text of all sections of this article has been updated, and typos have been corrected.]

















Examples of River Basins in the United States















ISSUES WITH THE MISSISSIPPI RIVER WATERSHED


The Mississippi River System is the largest drainage basin in the United States, receiving the water from over 40 percent of the country’s rivers.

The Mississippi River is mostly navigable by barges and it is heavily used for industry and transportation, carrying 60% of U.S. grain shipments, 22% of oil and gas shipments, and 20% of coal shipments.  It also carries large amounts of iron, steel, and mine products.



The Mississippi River is relied on for shipping, and it is kept in a navigable state by the Army Corp of Engineers in order for barges to be able to travel along the entire length of it.  Large scale ongoing public works projects are carried out where systems of locks, dams, riverbed dredging, and flood control measures are put into place.  The depth of the river is maintained at between 9 and 12 feet to accommodate the barge traffic.  (See this link.)

Sometimes the transportation interests of the river are at odds with water use interests upstream, especially during times of drought, when debates arise about what is the most important use of the water.








Nitrates from fertilizer runoff and other pollution from the Mississippi River are causing vast “algae bloom dead zones” in the Gulf of Mexico, where dense “phytoplanktons” grow and thrive on the surface of the water due to the increase in the nutrients, which harms fish and causes low-oxygen areas on the sea floor.  See a Wikipedia page about the issue at this link.






Issues with crops grown in the Mississippi River Basin


Following are points from this 2012 National Geographic Article:

— Lakes in Iowa are becoming overrun with foul-smelling algae due to fertilizers that are running off from cropland into the rivers.

— Nitrate and phosphorus fertilizers are cheap for farmers to purchase and use, but it is very expensive to clean the chemicals out of waterways and drinking water.

— The Mississippi River Basin grows a large amount of agricultural products, with farms to the west of it often relying on irrigation.  [(Note most of the irrigation water comes from underground aquifiers rather than rivers.)]

— The agricultural runoff eventually ends up in the Gulf of Mexico, where it causes large areas of “dead zones” in the water that suffocates marine life.

— Nearly four out of 10 ears of corn in the world comes from the Mississippi River watershed.  Most of the country’s corn, grain, livestock, poultry, cotton, sorghum, and soy is grown there as well.

— 60% of America’s “water footprint”— meaning their impact on water resources— is in the Mississippi basin.  Also agricultural exports can be thought of as “virtual water” being a part of the “water footprint” of the countries that receive the crops.

— Rice growing in Arkansas over the past century has depleted the groundwater aquifer [(See this link)], so now the heavily subsidized crop is increasingly irrigated with water that is diverted from rivers, which is causing wetlands to dry up.

— Marine life in the Gulf of Mexico is being adversely affected by the dead zone, including oysters and various types of fish.

— Most of the corn production in Iowa is used as fuel for vehicles or for feeding livestock rather than to feed humans.

— U.S. Water practices have allowed freshwater to become America’s single most degraded ecosystem, and the U.S. is in need of a “shared water ethic.”

— If corn growers raised alfalfa instead of soybeans to be used as animal feed, they could stop nitrates from leeching into the groundwater as well as improve their corn yields.  However, alfalfa only has a tiny market as most meat producers prefer to use corn or soy.

— If farmers planted cover crops of rye after harvesting their corn, it would stop a lot of nitrogen from leaking into rivers.  Also when the rye is tilled into the ground in the spring it acts as a natural fertilizer, however farmers find using synthetic fertilizers to be cheaper and less labor intensive.

— Most farmers tend to implement environmentally clean practices only if they have economic incentives to do so.










ABOUT THE SUSQUEHANNA RIVER IN THE NORTHEASTERN UNITED STATES





I’ve lived close to the Susquehanna River for more than thirty years, and I always wondered why the river isn’t usually used as a source of irrigation.  After looking into it I’ve found that the reason is mostly because of pollution issues, with the most significant sources of the pollution being agricultural runoff and the output from outdated municipal sewage systems in the region.  This article section explains aspects of those issues, including how to potentially fix them.

The Susquehanna River runs from New York State to the Chesapeake Bay in Maryland, being the longest river on the east coast of the United States that runs into the Atlantic Ocean.  Geologically speaking it is considered to be one of the oldest rivers in the world, and it is said to be the longest unnavigable river in the world.




Water from much of central New York State and all of central Pennsylvania drains into the Susquehanna River.  In Maryland the Susquehanna essentially becomes the Chesapeake Bay, supplying much of its fresh water.


A map of the Chesapeake Bay watershed, showing the Susquehanna River drainage basin in Pennsylvania and New York.  (Note I have added numbers to the map to identify the locations of the pictures in this section.)  Image: U.S. Department of Agriculture Natural Resources Conservation Service (link).


The water of the Susquehanna is clean enough to support an aquatic ecosystem along its length, although fish are being found in the river with diseases resulting from pollution in the water.  The main branch of the river from the north contains agricultural runoff from farms, urban and suburban stormwater, and it also receives the treated (and sometimes untreated!) water from the municipal sewage systems that are located within its drainage basin.



Here is a satellite image of the confluence of the western and eastern branches of the Susquehanna River in Sunbury, PA.  Notice that the water from the western branch of the river is very clean due to it originating in the sparsely populated State Game Lands of PA.  The merging of the water of the two branches can also be noticed when driving over the bridges.









Issues with the Conowingo Dam and its reservoir on the Susquehanna River

In 1928, the Conowingo Dam was built on the Susquehanna River in Maryland ten miles upstream from the Susquehanna’s mouth at the Chesapeake Bay.  The dam forms the 14 mile long Conowingo Reservoir, that supplies the drinking water for Baltimore.




Environmentalists are concerned that migratory fish species, especially the American Shad, have been blocked by the dam from swimming upstream in the Susquehanna from the ocean to spawn, which has prompted the construction of various techniques to allow the fish to pass upstream from the dam, which has had mixed results.  (See this link.)

The Susquehanna River floods very frequently, requiring the operators of the dam to open the floodgates during those times, which causes concern among environmental groups about the amount of polluted river water that is abruptly released into the Chesapeake Bay.

[The Wikipedia Page about the Conowingo Dam explains that the dam “traps sediments and nutrients that run off from the watershed and prevent[s] some of that from reaching the Chesapeake Bay,” although I wonder how the dam could actually hold back any significant amount of pollutants since the river is presumably constantly flowing through the dam and into the bay.]



A satellite image of the Susquehanna River feeding into the Chesapeake Bay.  Note the river water diffusing outward into the bay.  Image: Wikipedia.









The issue of outdated “combined sewage system overflows” releasing untreated waste into the Susquehanna River



A “combined sewage overflow” outflow pipe.  Image: osc.ny.gov.

The Susquehanna River drainage basin has many antiquated “combined type” municipal sewer systems that normally release both their treated water and stormwater into the river and its tributaries.  These systems had been mostly constructed during the 1800’s, being the preferred method that was implemented in urban areas of the United States at the time.  During times of heavy rainfall, deluges of stormwater can inundate such systems and cause them to release untreated raw sewage into the river, which is known as a “combined sewer overflow” (CSO).  Such releases are inherent in the design of the systems and they are accepted as a necessary evil due to budget limitations that stop municipalities from replacing the systems with modern designs that do not overflow in such a manner.

Rather than replacing such systems, municipalities often implement cheaper workarounds that reduce the amount of spills but do not stop them from happening entirely.  Operators of such systems are now required by law to issue alerts whenever such sewage overflows occur, which can happen during any large storm or flood.




























Issues with the Susquehanna River frequently flooding

The Susquehanna is one of the most flood-prone rivers in the United States.  Its banks become swollen after almost every large rainstorm that happens upstream, and serious floods have happened at a rate of once every fifteen years since the 1800’s.




The above video shows a variety of scenes of extreme flooding that occurred on the Susquehanna River in July of 2018.  The footage was recorded about ten miles north of the mouth of the river.





The above video shows arial footage of flooding that occurred on the Susquehanna River in 2011.











A theoretical concept of increasing the availability of river water for irrigating crops


It would be great if water from rivers in the U.S. could increasingly be utilized for irrigating crops, especially in the eastern U.S. where river water is very abundant.  However, many rivers such as the Mississippi (and in Pennsylvania the Susquehanna River, for example) usually aren’t clean enough to be used to safely irrigate crops, although such water is often used for that purpose anyway.  Much of the rice crops that are grown in the southern part of the Mississippi basin are often irrigated with polluted river water, for example.

Nonetheless, it could eventually potentially be ok for water from those rivers to be used to irrigate crops, assuming that measures would be taken to ensure that the water would be clean enough to be used for that purpose.  As a means of achieving such additional irrigation in an environmentally safe manner, perhaps river water could be pumped and stored into reservoirs that would be established to hold the water before it is sent out to irrigate crops, with the reservoirs serving to ensure that the water is free from contaminants before it is allowed to be distributed for use.

Most of the eastern United States receives a significant amount of rainfall when compared with the western and midwestern U.S., however many types of crops that can be grown in the East would nonetheless have increased yields if they could be irrigated with additional water.






Above is an illustration of the Susquehanna Valley, showing the reach of a theoretical implementation of systems for irrigating crops with water from the river (assuming the water quality could first be improved to be clean for that purpose).  Areas in green indicate regions where crops may potentially be able to be irrigated with river water based on existing topography.  The Yellow region is the actual watershed area that feeds the Susquehanna River with its water.  Source of the base image: Wikipedia.


Following are aspects of a theoretical plan for capturing and distributing river water for irrigating crops in an environmentally friendly manner:

— Guidelines could be established for three “grades” of irrigation water based on its cleanliness.  The highest grade should indicate the cleanest “drinkable or close to drinkable” water that could be used to irrigate edible crops; a second grade could be established for relatively clean water that also meets high standards that would be acceptable to irrigate non-edible crops (such as hemp, that could be designated as “non-edible” in that case); and a third grade should be designated for water that is deemed “too unclean for any purpose,” and their rivers should be targeted as a priority for being cleaned.  Edible crops that are currently being irrigated with polluted water (as rice and other crops often are in parts of the U.S.) should no longer be allowed to be irrigated in such a manner, and such farmland should be converted to only growing crops that would be designated as “non-edible.”

— The water of the river in question must initially be clean enough to be able to be used for safely irrigating crops, and if it does not meet high enough standards then the sources of the pollution in the river should be eliminated or greatly reduced before implementing any of the further steps of this plan.  The fact that such water could be used for irrigating crops should encourage people to become more aware of the importance of improving the cleanliness of the river and of all other such waterways.

— Large temporary holding reservoirs could exist that would have their bottoms lined with concrete, where incoming water would be held and tested to ensure that it would be safe enough to be released into larger adjacent reservoirs that would be used for long-term storage as well as for additional purification of the water.  If the water in the temporary reservoirs is tested to be too unclean, then it should be released back into the river.  River water could be pumped into such temporary reservoirs for testing whenever the banks of the river are at high enough levels (often whenever it rains upstream).  Perhaps even just a few days of swollen river banks could theoretically be able to fill large reservoirs with enough water to irrigate crops for many miles outward from the banks of the river for long periods of time.  (However it would not be safe to use water captured during floods in most rivers, because such water is usually toxic due to municipal sewer overflows and sources of toxic chemicals being submerged in the floodplain.)

— Townships along the banks of the rivers could maintain pumping stations that are distributed at frequent intervals.  Such pumps should continually be testing the water for contaminants, and they should be designed in a way to ensure that they do not harm fish or other wildlife.

— Large wetland areas could be created at the locations of the long-term reservoirs, that would additionally help to purify the water and also support a lot of wildlife.  Many types of birds and other animals depend on the existence of wetlands to survive.  More than half of the original wetland areas in the United States have been destoyed by being drained and filled in due to incorrectly being regarded as wastelands.

— The more the pumping and water storage infrastructure is built over time, the farther out from the banks of the river the water could be be available for irrigation.  Perhaps eventually river water could be used to safely irrigate crops for many miles out from the banks of most major rivers in the eastern United States, including along the Mississippi river and its tributaries.







Issues with underground aquifers, and an alternative concept of harvesting rainwater over active agricultural fields