Diamond Lake, OR

Hello fellers,

In the end of August I will be having my bachelor party at Diamond Lake in Oregon. I understand it has come on quite strong since being poisoned to get rid of the chub population.

I've done some research on the lake, looks like a big chironomid lake. I'm sure leeches and damselfly nymphs wouldn't hurt to bring either.

Can anyone else offer any insight into Diamond Lake?

How does it fish in late August?

If you were going to have to tie enough flies so a bunch of people could fish for three days, what patterns would you do?

Thank you in advance

Jim Wallace

Smells like low tide.
Can't remember which issue, but there was an article on one of the mags a couple of years ago about Diamond Lake.
I remember something about finding larger clear spots in the weeds, and fishing those holes, or along the outer edges of the weeds.
There's a fly fishing guide there, who takes clients out in his boat, and he either wrote the article, or was interviewed by the author.


Active Member
Lots of fish there, south end is the best fly fishing, good hatches. I remember seeing the largest calibaetis hatch I ever saw on a lake there, but no fish after them, surface temp was too high. I don't know about late August but you may have to go deep for the fish or the temps may be coming back down a bit because of the elevation. The resort has up to date fishing reports, but they are also in the business of renting rooms. The Ifish board often has reports in their trout yak section. You might post on westfly board too. There are more Oregon guys on that board.


Active Member
Diamond fishes very well in August most years. By August the bloom will start to lessen and the fish will start to put on the feed-bag for the coming Winter.

The south end is your best bet but you may have to hunt around a bit to find the fish. The whole south end east to west is a giant gently sloping shoal. You'll be several hundred yards off shore and only be in 10' of water. The east side of the south end has heavy weed beds while the west side of the south end has progressively less vegetation. As I mentioned, the fish can be found in different areas from year to year. A good bet is to find 10'-11' of water and move east & west looking for the fish.

Hanging pupa can be lights out in August but the lake fishes inconsistently. One day you'll have 50-take-downs, and the next day you may have 10. I like #14s in the late Summer & Fall, but one of the better fly fishers I know on Diamond has been doing very well lately with #12s.

Everything from bloodworms to various colors of pupa will be the "hot" fly for the day. Also, like any stillwater, some days the fish are close to the bottom, and some days you'll be in the "zone" 3-feet off the bottom.


Here are a couple photos of Diamond fish I released last August. These are the sort of Rainbows you might encounter hangin' pupa at Diamond. :)

Sweet fancy Moses! Those are some piggies!

Thanks everyone for the info. I talked to a friend who fished there last year and he also said south side, and fish any type of leech or sno-cones, red, size 16. To i guess i'll just tie up a bunch of them from 12-16 and call it good. My only experience with Diamond was back when, and don't tell anyone, i fished it with powerbait, back in the dark ages before i discovered fly fishing. I have always been curious to go back and fly fish there.

pond monkey

Active Member
Late august is getting into prime time as I see it..... bigger fish, nicer weather ect. Also the callibaetis hatch could very well offer a nice opportunity to match the hatch as it continues on into early september anyway.... no guarantees but you there is at least a 50% chance that the a hatch could develop during your visit.....It doesn't usually come off 'til 1:00 or so.....and it can sputter along for three hours...
I think there are bigger, fatter, healthier fish this year over previous years..... I am guessing that it is due to the State cutting back significantly on fingerling plants during the past couple of years and an increasing the bag limit to eight... resulting in fewer but chunkier fish....a good thing...
Have fun....PM


New Member
The advice from sinkline and pond monkey should be taken seriously as both are good stillwater fisherman and know what they are doing. I am less experienced but still fish Diamond a couple times per year and usually do OK. This year, from what I saw, the lake's calendar started early. The big midge hatch went off earlier, the skeeters came out in force earlier (At one point I had over 30 bites on my body and then stopped caring) and the fish went into summer mode earlier. For me, mid summer has proven a really tricky time to catch trout on flies at Diamond. You will see nice hatches and not a fish on the surface. When we catch and keep a fish it is packed with only snails. The fish seem to hunker down during the warm water months and for me at least are harder to catch. Trolling (either wind, electric motor or with leg power) still usually brings us a few fish.

When you time the midge hatch correctly (like sinkline says above) it can be lights out, fish every couple casts or few minutes. My limited experience in the last summer has been that moving around is better than hanging flies below bobbers, but I know if you get your locations dialed in, the indicator method still is very good. I don't fish it enough to know the honey holes.

Whatever you do, have a great time, don't celebrate so much you can't fish (first hand experience here) and enjoy your time. It is a cool place.