Lake Pactola in the Black Hills of South Dakota

[2airishuman]

Well, I'm back from the Hill City/Rapid City area and have a few things to report.

Air fills and other support

There is no local dive shop. I brought 7 full cylinders from Minneapolis and emptied all but one.

I encountered several local divers before and after my dives. Closest dive shop is in Pierre. I was told that there is a local dive club that purchased the compressor from the now-defunct Black Hills Scuba, but it's unclear how active they are, and I wasn't given (and can't find) any contact information.

There is a Pennington County/Rapid City water rescue team who could be a source of further leads or access to public safety air sources.

Pactola Reservoir

I dived Pactola on two different days. There is a $6 cash parking fee to park at Pactola Point beach, which I found to be the most practical location for shore dives. There isn't anything notable right at shore, but there's good visibility by freshwater standards. At shallow depths there are fish and some moderately interesting vegetation temps around 70, deeper there are stumps left over from before the dam was completed, fewer larger fish, and not much more. I planned my second dive to 80', by which time the temperature was around 45 and the light dim.

Sylvan Lake

This small man-made lake within Custer State Park is a real gem for outdoor recreation in general. The lake has a swimming beach but also features sections with sheer walls, and there are several reefs and islands with sheer sections extending below the surface of the water. There are a few fish but there also large crayfish everywhere. Never seen so many or such large ones. I brought a trash bag on one dive and brought up two cell phones, a rudder, half a kayak paddle, and various cans, bottles and other junk. I don't think the lake gets very many divers. Depths to about 30', viz not as good as Pactola, maybe 5', but the more varied underwater topography makes up for it. There is no motorized boat traffic on this lake but it is popular with kayaks and stand-up paddleboards. Temps low 70s

Cold Brook Reservoir

This impoundment, intermediate in size between Pactola and Sylvan, had the best visibility and most fish. Viz about 20' in places, rainbow trout, some branches and construction leftovers in an otherwise clean lake. Depths to about 40', possibly deeper near the outlet, which I was avoiding for safety reasons since I didn't have any information on its hazards or lack of them.

Cold Brook Reservoir is located near Hot Springs. Wind Cave National Park is also nearby.

All together, a fantastic and varied bunch of freshwater dives. If you're in the area, bring your gear and some air.

Thanks to @DA Aquamaster for information on local diving before my trip.

 

[kman779]

Sorry to post on an old thread, but I wanted to make sure this information got posted in case someone like me ran across this discussion. There is a new dive shop in Rapid City: Black Hills Aquatic Adventures. Home

The shop is run by locals who are much more active than the previous dive shop owners. They are full service and make frequent trips to Pactola for NAUI and Public Safety diving courses as well as events.

 

[divad]

Sorry to post on an old thread, but I wanted to make sure this information got posted in case someone like me ran across this discussion.

Everybody likes a feel-good story (even cynics). Neat to have a nice dive site and a good shop.

 

[2airishuman]

We will be diving in the area next week.

 

[DA Aquamaster]

Cold Brook Reservoir

This impoundment, intermediate in size between Pactola and Sylvan, had the best visibility and most fish. Viz about 20' in places, rainbow trout, some branches and construction leftovers in an otherwise clean lake. Depths to about 40', possibly deeper near the outlet, which I was avoiding for safety reasons since I didn't have any information on its hazards or lack of them.

Cold Brook Reservoir is located near Hot Springs. Wind Cave National Park is also nearby.

I can add a few comments about Cold brook. The outlet is basically a stand pipe where water flows over the top, maintaining a constant maximum water level. It's not a threat to divers and there are usually some large fish hanging out around it.

The bottom is generally sand and silt with a fair amount of vegetation, given the fairly shallow depths. 35-40 ft is about the maximum depth for vegetation in the area, as there isn't enough light deeper than that to support much growth of green plants.

Visibility is more consistent than Pactola and 20'-30' is pretty average. Between the consistent visibility, the OW friendly depths and the warm in the summer water temps, it used to be a popular site for dive training in the area. Take this all with a grain of salt as it's been 10 years since I last dove there, so some aspects may have changed.

 

[DA Aquamaster]

Sorry to post on an old thread, but I wanted to make sure this information got posted in case someone like me ran across this discussion. There is a new dive shop in Rapid City: Black Hills Aquatic Adventures. Home

The shop is run by locals who are much more active than the previous dive shop owners. They are full service and make frequent trips to Pactola for NAUI and Public Safety diving courses as well as events.

That's welcome news. There is some good diving in the area, and there used to be a fair number of active dives.

Things started sliding down hill when the area lost one of it's shops and quickly plummeted over the edge when Mike sold the remaining dive shop. It's new owners offended me enough with their unfriendly and non customer centered business practices to inspire me to buy my own compressor and not bother ever darkening their door again. I hate to see any dive shop close, but I made an exception in their case.

 

[2airishuman]

Dive reports.

Pactola -- unchanged since last year. Viz at least 10' near Pactola Point and variable with depth and location. Lots of fish in places, interesting bottom topography. Recommended.

Cold Brook -- unchanged since last year. Viz around 15', abundant fish. Also recommended.

Sylvan Lake - viz 2-3', probably due to unusual weather patterns. The lake had been closed to swimming a few days before I dove it due to high bacteria counts. Found two nice U.S. Divers masks and an inexpensive fishing rod complete with reel, bobber, sinkers, and hook, all of which I gave away. Also a nice collapsible canoe paddle. I am easily entertained by such finds, but the diving is otherwise unremarkable.

Center Lake - viz around 4', found a nice graphite fishing rod and spinning reel and one of those step-in fishing rod holders right next to it -- the kind that you push into the ground with your foot to hold your rod while shore fishing. Dive was otherwise unremarkable.

Horsethief Lake - good viz (5'-8') near the surface with viz deteriorating badly below the thermocline at about 10 feet. Not much to see and surprisingly little in the way of finds.

 

[DA Aquamaster]

.../

/...Sylvan Lake - viz 2-3', probably due to unusual weather patterns. The lake had been closed to swimming a few days before I dove it due to high bacteria counts. Found two nice U.S. Divers masks and an inexpensive fishing rod complete with reel, bobber, sinkers, and hook, all of which I gave away. Also a nice collapsible canoe paddle. I am easily entertained by such finds, but the diving is otherwise unremarkable.

Center Lake - viz around 4', found a nice graphite fishing rod and spinning reel and one of those step-in fishing rod holders right next to it -- the kind that you push into the ground with your foot to hold your rod while shore fishing. Dive was otherwise unremarkable.

Horsethief Lake - good viz (5'-8') near the surface with viz deteriorating badly below the thermocline at about 10 feet. Not much to see and surprisingly little in the way of finds.

Those are pretty typical conditions in the summer in many of the smaller and or shallower lakes in the area. You got lucky last year if you had better viz at Sylvan Lake.

Shallow lakes, or lakes with large areas of shallow water in that area end up with higher water temps, and warmer water has lower levels of dissolved oxygen which causes the fish and/or mussels in the lake to die off, which causes the rise in bacterial levels. I normally only dove those lakes if someone lost something in them and paid me to dive there.

At one point the US Forrest Service hired me to recover a bunny bucket that a contract pilot had pickled by mistake. Since they had a large wildfire burning out of control at the time they wanted it recovered right now. The lake in question was shallow (about 6'-8' deep in the area where they lost it), but was covered with foot tall stumps which made finding the bucket very difficult given the viz was also zero. The pilot also had a very poor idea where he was actually hovering when he lost it. The end result was I was poking around in 85 degree water and dead clams for about 6 hours in a dry suit and full face mask. The USFS folks flew home in their helicopter leaving me with a three hour drive back from the boonies. Shortly after they left, I realized my throat was swelling shut and I just made it to the nearest ER in time.

Pactola is unique in that it's 150' maximum and 100' average depth in the main basin helps keep the lake cool and produces enough turn over to keep oxygen levels suitably high.