Visiting Oroville Dam: The Tallest Dam in the Country

Oroville Dam has been the crown jew­el of the State Water Project, and man­aged by California’s Depart­ment of Water Resources (DWR), since its com­ple­tion in 1967. The eye-pop­ping num­bers alone might seem like enough to appre­ci­ate the sheer size of the struc­ture: at 770 feet, it’s the tallest dam in the coun­try and retains the con­tents of Lake Oroville—about 3.4 mil­lion acre feet — dis­trib­ut­ing the water to the entire Sacra­men­to Valley.

But a vis­it to the dam — where no few­er than a half-dozen ​“wow” moments await vis­i­tors, espe­cial­ly those who choose to get a guid­ed tour from DWR staff — is real­ly need­ed to under­stand just how big the dam is. That’s the route I went on a cold Jan­u­ary day ear­li­er this year, and from the very begin­ning of the tour, it was clear to me how easy it is to take this behe­moth for granted.

For more than 50 years, the Oroville Dam has devel­oped and shaped the town’s his­to­ry, and the two are insep­a­ra­bly linked — from the high-water marks locat­ed across town to the orig­i­nal green bridge that still stands, cross­ing over the Feath­er River on Mont­gomery. Our tour start­ed here, look­ing at the bridge from under­neath and tak­ing note of the high-water marks and debris scuff­in­gs that char­ac­ter­ize the bridges’ sup­ports. From this van­tage point, it was easy to imag­ine just how much water moved through this stretch dur­ing North­ern California’s his­tor­i­cal floods.

When I took a moment to con­sid­er how much water the Oroville Dam is respon­si­ble for stor­ing — a stag­ger­ing 1.1 tril­lion gal­lons — I couldn’t help but mar­vel at how rel­a­tive­ly infre­quent­ly those major flood events actu­al­ly happen.

It’s because the dam is much more than sim­ply ​“big.” Its his­to­ry as a major source of employ­ment dur­ing its con­struc­tion is awe-inspir­ing when con­sid­er­ing how the bar­ri­er (a most­ly con­crete core) was rein­forced with man-made earth­en sup­port — an esti­mat­ed 80 mil­lion cubic yards of earth, all orig­i­nal­ly filled one truck­load at a time. 

A wind­ing dri­ve up the dam’s moun­tain­ous ascent, above the spill­way (and, exhil­a­rat­ing­ly, past the spill­way gates), is a hum­bling and awe­some les­son in scale. You get a passenger’s‑seat view straight down the spill­way. Even for some­one with an appre­ci­a­tion for the structure’s immense size — longer than 1,000 yards — I stared in amaze­ment at the sheer mass of con­crete yawn­ing down the side of the dam like a 12-lane super­high­way. A lit­tle fur­ther up the road, what looks like a sprawl­ing, con­crete amphithe­atre appears; this is actu­al­ly a sec­ondary emer­gency over­flow area. Like just about every­thing else attached to the dam, it’s enormous.

I took all of this in while our guide, DWR’s Jana Fra­zier, dis­played an ency­clo­pe­dic knowl­edge of the dam. She gave us lessons rang­ing from agri­cul­tur­al to zoo­log­i­cal and a dozen oth­er top­ics in between, all relat­ed to the dam and its impact on the many inter­con­nect­ed sys­tems rely­ing on it. I tru­ly appre­ci­at­ed the amount of con­text I was able to give what I was see­ing, thanks to Frazier’s expertise.

Atop the dam, I had only one regret: I wished I’d brought a good cam­era and binoc­u­lars. The van­tage point from 770 feet offers 360 degrees of view­ing, and even as a brisk win­ter wind whipped around the park­ing lot and dri­ve, it was easy to imag­ine a sum­mer day in the same loca­tion. My mind start­ed piec­ing togeth­er options for a vis­it — a pic­nic lunch at one of the rest areas atop the spill­way; a bike ride or a hike down some of the eas­i­ly acces­si­ble paths right off the launch ramp; a few moments spent admir­ing the vis­tas to the south or the hawks (or occa­sion­al eagles) glid­ing across the lake. But on this day, where no warm-blood­ed per­son would be seen on the water, Lake Oroville was a pic­ture of seren­i­ty, a glass sur­face pierced only by the occa­sion­al jump­ing fish or water­fowl touch­ing down.

What every­one knows about the Oroville Dam, of course, is that it’s immense. But my tour of it revealed more than just sheer size: It offers his­to­ry, beau­ty, and a sense of appre­ci­a­tion for the dam’s role in the Cal­i­for­nia ecosys­tem. To stand atop the dam and gaze over not just the wide expanse of Lake Oroville, but also the val­ley to which it’s so cru­cial, is an exer­cise in won­der­ment that shouldn’t be missed.