There is a line from James Weldon Johnson’s telling of the Creation Story that has been playing in my brain for decades. I have read that poetic telling in the style of an African-American preacher in the time of slavery over and over again. We used to use that version as part of our celebration of the Great Vigil of Easter and at other occasions as well. There are many lines from that poem that I have memorized, but the one that often plays in my mind as I walk through the corners of Creation that I have been privileged to visit is this:

The lakes cuddled down in the hollows of the ground,
And the rivers ran down to the sea;

I am often mesmerized by water. I grew up next to a river that flows from the high country through the mountains and down to its confluence with the Yellowstone River in Montana. The Boulder River is aptly named as its bed is full of river rocks, some of which are larger than the pumpkins people are carving for Halloween. When the river is at flood, you can hear the boulders crashing down the river with a music all their own. The river that flows by the place of my childhood summers is one of two in Montana of which I am aware that have the same name. The other one also has its share of boulders.
I have been lucky to paddle on a lot of different lakes and down quite a few rivers. The movement of water is one of the songs of my life, but I also have been serenaded by the absolute quiet of a canoe on a lake at sunrise. I’ve learned to dip my paddle with almost no splash because of the delight of the quiet.
Lakes indeed do cuddle down in the hollows of the ground and rivers run down to the sea.
I, however, have lived most of my life a thousand and more miles from the sea and my imagination about how those rivers run down to the sea has been far less beautiful and far less complicated than the realities that I am discovering now that I am spending more time next to the coast.
Of course I learned about deltas in school, the Mississippi River delta being the primary example. The river carries all kinds of dirt and mud and sand as it flows along and as it enters the ocean it deposits those materials and the stream of water is divided as it flows around all of those deposits. Over the years the deposits form significant land mass and provide protection to inland places from king tides and even hurricanes. The altering of the Mississippi River system by upstream dams has reduced the flow of mud and dirt and affects the natural formation of the delta. This process is heightened by the creation of dams and levies designed to limit coastal flooding. The result has been a reduction in the protective effects of the delta. The delta itself is currently being washed away by natural ocean erosion and the effect is reducing the delta at a more rapid rate than it is being built up by the river. It is one of many environmental crises that have resulted from dense human population.
Not every river has a delta, however. I have followed the mighty Columbia river as it flows toward the sea for decades as I have driven to and from the coast where Oregon and Washington meet. We have taken multiple vacations to the cost near where the Columbia enters the Pacific Ocean. Many years ago, I had a series of meetings that were held at the Maritime Center in Baltimore, Maryland, where pilots are trained to guide large ships through tight harbors and dangerous currents. There is a significant display in the Center about the Columbia Bar Pilots and the history of their work. I met several of the pilots who were at the center for advanced training and have learned a bit about how the Columbia meets the ocean. The mouth of the Columbia is unusual for a big river because it has no delta. Instead, sediment is transported down subsea canyons to deep water, leaving the river mouth subject to waves, tidal flow, and currents. It's the most treacherous place for ships on the Pacific coast.
The lakes huddle down in the hollows of the ground and the rivers run down to the sea, but their pathways to the ocean are not all the same. Where we now live, we cross a tidal creek nearly every day when we are on our walks. I knew that tidal creeks and rivers existed, but I had never before spent time looking at them in such detail. Terrill Creek, which flows into Birch Bay a bit less than a mile from our home, is tidal for over three miles. That means that the water in the creek rises and falls with the tide. When the tide is rising the creek runs upstream to a slough three miles from the ocean. When the tide is falling the flow of the creek reverses and the fresh water from upstream flows back toward the ocean. The creek is a mixture of fresh and salt water over the course of the entire three miles and well into the slough. The amount of salinity varies with the time of the year and the time of day. The creatures that live in the water are a mixture of those adapted for living in the ocean and those whose lives are spent in fresh water. Most notable among those specialized creatures are the salmon who are hatched in fresh water and then swim out into the ocean for much of their lives, returning to the fresh water to spawn at the end of their lives.
Yesterday our walk took us to another way that the rivers run down to the sea. We walked alongside a large estuary. Dozens of acres of shallow water are fed by springs and at least three creeks that run down to the sea. The ocean tides rise and fall in the estuary which is rich environment for a wide variety of creatures. Despite the constant surf of the Oregon coast, the estuary is an area of calm interface of fresh water and ocean.

The rivers run down to the sea in many different ways and I am only beginning to learn of a few of those ways. It is a fascination worthy of the great poem.