Watered down taste??

Long story short: made a cascade pale ale partial mash, wort chiller leaked about an extra gallon of water into brew kettle. Ended up with six gallons, not five. Og was 1.045, was shooting for 1.052.

Is this going to make the beer taste watered down and less flavorful? I was hoping for a some cascade hop flavor and aroma, but I got a feeling this ruined it...

You could boil a little longer. At my house, I'd set it on the back deck and freeze off some of the wort before pitching the yeast. There would be 5 inches of slush on top by tomorrow morning.... ....useless extra water.

All kidding aside, Post your recipe and mash schedule.

It would probably be a nice lighter "session" beer as it sits.

Cascade pale ale

3.3lbs light lme
4lbs American 2-row malt
8oz carapils
8oz caramel 10L
3oz cascade hops
US-05 safale yeast 11.5 grams

IBUs = 48
OG = 1.052
AL % = 5.2%

Mash the 5lbs of grains with 1.6g of water at 152* f for 1 hr. Mash out at 170* f for 15 minutes. Vorlouf as needed until clear. Drain mash tun completely. Batch sparge with 6.5 gallons at 170* f for 15 minutes, stirring occasionally. Collect second runnings.

Boil wort, add 1oz cascade hops at 60, 15, and flame out. Add 3.3 lbs of lme at 10 minutes.

Looks like a nice Pale Ale to me. For IBU calculations, did the water get added post boil? Either way it's about 40-44 IBU.
You could add a pound of DME to beef it up if you want, but like was said, sounds like a nice beer as is.

I wouldn't consider that a watered down beer, but your taste may vary.

I wouldnt worry about it.

I wouldnt think it would give it a watery flavor.. but a lighter body.

No matter what it will still be beer

I got an extra 1/2 gallon in my first batch during the bottling phase.. (Long story, one of these days I will read directions better). Made my stout watery at first. But once the yeast carbed up the beer, and it aged a bit the watery flavor went away.

Since yours was added before fermentation, I would think you will be fine.

You basically added top up water in a way. Many people do this post boil to bring the batch back up to the volume they want in the fermenter. Definitely not a big deal, you'll be fine.