I recently talked with someone who had a lot of experience working in the Cahaba River watershed years ago. He preferred to discuss this anonymously, so we will call him Mike.

Mike remembers his father taking them camping, driving off-road in his ’48 Chevy (which is where they would also sleep). He fished often, and was bothered by the trash and pollution he saw. There were no programs to remedy this, so he decided he wanted to do something about it.
His formal secondary education was limited to classes he took at a local junior college to learn how to do upholstery (so he could replace the headliner in his truck), and welding.

The first chapter of his life working on the Cahaba was with water flow gauges. The gauge was comprised of a box several feet in length, height and depth and contained the recording instrument and a vertical pipe (with a float inside) which extended down to 6 inches off the river bottom. The box and pipe had to be welded onto the steel I-beams supporting the bridge. (This was done on the downstream side to avoid limbs and other debris the river was carrying along.)
Another important part of the gauge was a locked door to keep out animals and to deter vandalism. The main form of vandalism was people shooting at the meter box. Reinforcing the metal box was considered, but this idea was discarded because of concern about risks from ricocheting
bullets. Instead, when damaged, meters and boxes were replaced. Occasionally one had to be removed due to recurrent vandalism.
Each meter had a paper tape between two spools. The tape advanced and every 15 minutes would be struck and punctured by a spring-loaded pin, indicating the depth (and indirectly the flow rate of the river).

The team made visits monthly to each gauge. There were 8 that were serviced monthly (until the one on Black Creek had to be removed due to vandalism)- changing the 6 volt battery, removing the used spool of tape (which was taken back for evaluation) and installing a new one.
Their other task was to take manual measurements to confirm the gauges were measuring accurately. Readings were usually taken every half-foot across the width of the river. (At times, readings were taken at greater distances because of bad weather, or due to rocks which disturbed the flow near the bridge in a spot that was to be measured.) An average of the total flows was then calculated and compared to the meter’s reading. This brief explanation belies the effort required. Two people were necessary for the job. One noted the measurements and watched for snakes and logs coming down the river. The other person made the measurements. When water levels were low, this was done standing in the water holding a staff gauge (with attached meter) set on the river bottom. In high-flow times Mike would stand in the bed of a pickup truck atop a bridge over the river with a heavy salt-water fishing rod and reel attached to a rod on a swiveling base. The cable from the rod and reel connected to a 80-100 pound lead airplane-shaped weight which carried a meter down into the water. This meter was a vertically-oriented cylinder that had 6 or 7 cups in line around its circumference. The water flowing by was caught by the cups, causing it to rotate in proportion to the rate of flow. A pin would click with each revolution. This click was amplified and heard through headphones. The clicks were then counted to measure the flow. This was sometimes difficult due to rapid revolutions. Another challenge was cranking up the heavy weight quickly to prevent floating logs from damaging the meter. Measurement of river levels was most important when water levels were rising due to rains. This would often be a high-risk operation- Mike would be standing in a truck bed in lightning storms holding a rod attached to a cable that went into water!

In the 1970’s Mike participated in a federal program with the goal of water testing the water in the tributaries of the Cahaba River. The team included a chemist, a hydrologist, and a microbiologist (which he called “the fish guy”). Most of them were just out of college, in their early twenties. Although Mike did not have a degree, he had practical knowledge that benefited the team. They had to get supplies from backroads through the woods, and then travel down the streams. Madriver canoes were the vehicles they used. To sample streams more efficiently, they split into groups to cover four different areas at a time. One of the guys was overweight, and when in the canoe, made it impossible to keep it level (trim). He quickly became the designated “pick-up guy” who would meet them downstream to off-load the samples and pick them up when the day’s work was done. Being in the wilderness all day, they had to carry food and drinking water, as well as testing supplies. Taking some inspiration from an uncle he had visited at Fort Benning, GA, Mike went to an Army-Navy store and bought backpacks and canteens to simplify the process. He also impressed his co-workers when he used his lighter and a pan to heat up his lunch. (“I always had my lighter and knife with me”).

There were two tributaries Mike mentioned by name. On Black Creek, near Trussville and Leeds they found an un-mapped road and an old iron bridge. Turkey Creek, near Pinson, had popular swimming holes but was too cold for him. They once found small fish called darters. The fish guy wanted to keep some. They were transported back to the lab in pieces of a garbage bag which were filled with water. They set up an aquarium in the lab, and got some store-bought fish food, but the darters weren’t interested.

One of the main goals of the water testing was to measure the amount of oxygen in the streams and rivers. Oxygen levels indicate the health of the water system. Higher oxygen indicating less pollution and better conditions for life. At some point the project had a $1,000 DO meter for measuring oxygen concentrations, but didn’t dare trust it in a backpack or canoe, so it stayed in the lab. It was critical to get the samples back to the lab without any change in the oxygen levels. Prior to the sampling, the bottles were labeled. Samples were taken from different areas and placed in the appropriate bottles. BOD bottles (which I have learned stands for Biological Oxygen Demand) were the first part of getting the water back to the lab. They were made of thick glass and had a separate glass top which when pressed down sealed itself and pushed out all air. The other part of stabilizing the oxygen was a technique Mike said originated in the 1800s, called the Winkler method (https://serc.carleton.edu/microbelife/research_methods/environ_sampling/oxygen.html). Two milliliters of sulfuric acid was manually pipetted into each water sample before sealing the top- thus preventing changes in the oxygen level. The bottles were then placed in holes made in a styrofoam block that was wedged in the middle on the canoes. When the samples made it to the lab, the remainder of the Winkler chemicals were added and the oxygen levels measured. Prior to the acquisition of the DO meter, the last step of the testing involved slowly adding the last reagent through a calibrated burrette glass tube until the mixture turned clear. The amount of water added then allowed calculation of the oxygen level.

Later Mike did industrial pretreatment. He knew that some factories and treatment plants were being overlooked as potential sources for water pollution. So, he looked through the phone book to identify these industries. One of the things they did was to see what solid trash was being released into the watershed. An example of this was Bama Jelly’s production of blackberry jam. He found that the seeds were washed down the drains, eventually getting into the streams. A simple solution was to place a screen over the drains to catch the seeds. Their main technique was to put dye into the interior drains and then check the sewer manholes to see where the dye re-appeared. There had to be a manhole within 500 feet of the plant, and then every 500 feet for some distance. (“Finding those was a job!”)

Mike surprised me with a question near the end of our discussion:
“I want to know if all of our efforts were worth it… did it make a difference?”

I paused, thinking about how the Cahaba River has changed since the 1970s- how increased construction, stormwater runoff, and pollution have had negative effects. But then I thought about the successes of the Cahaba River Society, Cahaba Riverkeeper and many others who love and support the river. I assured him that his work was important and appreciated, and that many people are continuing the fight to protect the Cahaba River- as a major drinking water source, for its accessible and unique beauty and as one of Alabama’s (and the country’s) top natural resources.