Ayre

One of the most usable of the pleasant, newly adopted nature/water names (like Lake and Ocean), especially in middle position. 
 There was a character named Bay Kennish on the show Switched at Birth; conservative political commentator Bay Buchanan was born Angela Marie.
 Other associations with bay are the bay laurel tree, prized since ancient times for its medicinal and culinary (bay leaves!) properties, and the reddish-brown color usually applied to horses.

With the tide coming in on a new wave of word names, this one just might catch on, especially for parents who relish sun, sand, and surf. Forest lovers can spell it Beech, like the tree. 

Beach

A new name with the potential for spanning across a far-reaching future. Bridges and Bridger are other possiblities.

Bridge

Bight

Cay is a rare respelling of the retro nickname Kay but one that may gain ground as a name that's both simple and unique. Like Kay, it can be a diminutive for any of the hundreds of Catherine variations that start with a C or of more modern names such as Caylee or Cadence. Or it can stand on its own as a sleek contemporary nickname-name.

Cliff is a familiar, timeless short form -- never too popular, yet widely known -- that you might also think of as a geographical name ala Vale or Field.

Cliff

Cove is an up-and-coming nature name whose cool sound and peaceful image saw it rising for both sexes... until COVID-19 hit. It remained steady in use for boys in 2021, but actually increased for girls, although it remains a seriously rare and distinctive choice for either gender. 

Cove

Cape

Channel

Coast

Delta is an unusual vintage option with a lazy-day-down-by-the-river feel. Delta is the fourth letter of the Greek alphabet and also the geographical name given to an island formed at the mouth of a river. 

 Australian singer Delta Goodrem is a notable modern bearer.

Delta

Why did 5 sets of parents chose to name their sons Dock in 2016? We may never know.

Dock

Dune is a name of several layers. It's a modern nature name, like Ocean, Bay and Reef, although rarer, conjuring up images of breezy sand dunes on summer beach days.
 
It's also assocated with Frank Herbert's Dune iconic series of sci-fi novels. The name increased in popularity in 2021, when the most recent movie adaptation was released.

Dune

Dockyard

Firth

Fjard

Fjord

Gulf

Harbour

Island

Isle

Jetty

Keys

Evocative modern unisex choice brought into the spotlight by actress Lake Bell. 

Lake

Loch is a watery word that sounds more like a name because it's one step removed from its English form. Pronounced as "lock," it's also a short form of the variously-spelled Lachlan.

Loch

Lagoon

Soft and mellifluous nature-surname name, situated miles away from the dated Marshall. 

Marsh

Mangrove

Ocean is a nature name that comes right out and states its meaning and association. Full of power and depth, Ocean is one of the fastest-rising baby names for both girls and boys, making the US Top 1000 for both genders in 2021. Oceane, the version that's trendy in France, was used for only 11 baby girls in the US in the same year.

Ocean-lovers who want to be less obvious can choose such subtler <a href="https://nameberry.com/list/641/names-that-mean-ocean">names that mean ocean</a> as Jennifer or Marissa, but coming right out and using Ocean is a perfectly valid way to go.

Ocean

Port

Pond

Pool

A name that looks intriguing and masculine on paper, but is, unfortunately, a homonym for a girl's name. 

Quay

Modern surfer boy. Just don't call him Reefer. 

Reef

Most of the notable Rivers have been male, but this nature name certainly flows as well for a girl. The name River is still rising for both genders, with about 3500 baby boys receiving the name last year vs. 1900 baby girls.

Kelly Clarkson's choice of River for her newborn daughter further raised the profile of the <a href="https://nameberry.com/girls-names">name for girls</a>. Baseball great Derek Jeter and Hannah Davis used the same name as Clarkson for their daughter born in 2021, River Rose.

River

Riptide

Spring doesn't sound half as contemporary as Winter, which has become the cool season name. 

Spring

Shack

Shipyard

Shoal

Shore

Sound

Strait

As likely to be tied to the detergent as to the rhythms of the ocean. 

Tide

Wave

Wharf

Yard

vintageluvs's list "Nautical Names - Geographical Names" of 50 great name ideas: Ayre - Yard!