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Understanding California's Bay Delta in 63 Photos

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An explanatory series focusing on one of the most complex issues facing California: water sharing. And at its core is the Sacramento-San Joaquin Bay Delta. 

In the world of California water, much of the conversation -- nay: argument, really -- centers on this place called the Delta. Northern Californians think Southern Californians want to drain it dry. Southern Californians, for the most part, don't even know where the Delta is, much less why it would be important to them. I'm just guessing, but I would be willing to bet that most Californians who don't live near the Delta don't know where it is or why it is important, either.

So in this post, using pictures of my own and borrowing a few pictures from others, I will try and answer the question, what is the Delta and why is it important?

First of all, let's take a look at where the Delta is.

1. The Delta encompasses 738,000 acres.

Map of the Bay Delta

It stretches inland from Antioch to Stockton, and from Sacramento and West Sacramento at its northernmost point down to Tracy at its southernmost point.

2. Five rivers flow into the Delta, accounting for nearly half of the snowmelt and runoff of the entire state. The most noted are the San Joaquin and Sacramento rivers. The other three are the Mokelumne, Cosumnes, and Calaveras rivers.

Satellite Photo of Bay Delta Detail

Because the Delta is connected to San Francisco Bay, and thus to the ocean, it is affected by tidal action. Although the Delta, for the most part, remains freshwater, this tidal action affects the depth of the waterways. There are approximately two high tides and two low tides every day. Photo: Courtesy USGS

3. Once a vast marsh, the Delta began changing rapidly when unsuccessful miners turned to farming and began draining and reclaiming the land in the mid 1800s.

Photo of Holt Steamer, Crawler-type Tractor Prototype

They were encouraged by federal swampland reclamation laws and the Delta's rich, fertile peat soil. They built levees, creating islands of productive farms. The reclamation of the marshy Delta progressed steadily for many decades, and was pretty much complete by the 1930s. Photo: Public domain/WikiMedia.

4. This is what the Delta looks like today from above. It is a maze of over 1,100 miles of waterways that traverse prime farmland and natural habitat areas, with levees surrounding numerous islands or tracts.

Aerial Photo of Bay Delta

Photo: Chris Austin

5. Some islands are only accessible by private boat.

Photo of Delta Waterways with Small Dock

Photo: Courtesy Department of Water Resources

6. And some of these islands are only accessible by ferry.

A Ferry on the Bay Delta

Photo: Chris Austin

7. While others are connected by drawbridges and bridges.

Drawbridge on the Bay Delta

Photo: Chris Austin

8. There are many kinds of bridges.

Split-screen Image of Bridges

Photos: Chris Austin

9. The Delta is an estuary, which is the body of water that is formed when freshwater from rivers and streams meets the ocean and mixes with the salty sea water, creating a vibrant ecosystem.

Aerial of Bay Delta Estuary with Birds in Flight

Photo: Courtesy Department of Water Resources

10. The California Delta, along with the San Francisco, San Pablo, and Suisun bays, is the largest estuary on the Pacific Coast, and is home to over 750 plant and animal species.

Satellite Detail of the San Francisco Bay, San Pablo Bay and Suisun Bay

Map: Courtesy USGS

11. The Delta is home to a vibrant diversity of wildlife and birds...

Blue Heron in Flight

Photo: Courtesy Department of Water Resources

12. ... including millions of migratory birds who stop over on one of the last remaining wetland areas on the California coast.

Birds in Flight

Photo: Courtesy Department of Water Resources

13. Sandhill cranes, one of the oldest living species of birds, arrive about late September to spend fall and winter here.

Four Sandhill Cranes

Photo: Courtesy Department of Water Resources

14. The Delta supports vibrant commercial and recreational fisheries. Eighty percent of the state's commercial fishery species either live in or migrate through the Delta, including four Chinook salmon runs, sturgeon, and striped bass.

Salmon Under Water

Photo: Courtesy Department of Water Resources

15. There are numerous opportunities for recreation in the Delta. The labyrinth of sloughs and waterways in the Delta make it a prime place for boating and waterskiing.

Waterway with Trees in Foreground and Power Boat in Distance

Photo: Chris Austin

16. There are over 100 marinas and waterside resorts, RV Parks, grocery stores and dock-side restaurants.

Aerial Photo of Delta Marines

Photo: Courtesy Department of Water Resources

17. The Delta's frequent winds make for ideal sailing and windsurfing conditions.

Two Sailboats on the Water

Photo: Chris Austin

18. Fishing is popular here, too.

Wading Fisherman at Dusk

Photo: Courtesy Department of Water Resources

19. The Delta's islands are, for the most part, sparsely populated.

Delta and Islands with Few Dwellings

Photo: Courtesy Department of Water Resources

20. You can seemingly drive for miles on winding levee roads and not encounter another soul.

Delta Waterways and Bends

Photo: Chris Austin

21. It is a wondrously peaceful place.

Delta Grasses and Plants

Photo: Chris Austin

22. Inside the Delta, there are small villages and towns...

Villages, Towns, Farmland along the Delta

Photo: Courtesy Department of Water Resources

23. ... many of which have been here since the beginning.

Old-Looking Buildings and a Sign Reading "Chinese Cultural Shop"

Photo: Chris Austin

24. Modern urban development is increasing inside the Delta.

Newer Homes and Businesses along the Delta

Photo: Courtesy Department of Water Resources

25. But the main land use by far in the Delta is and always has been agriculture.

Delta Slough with Grasses and Crops

Photo: Courtesy Department of Water Resources

26. Most of the islands in the Delta are used for farming. Many of the farms have been held by the same family for generations.