We had a chance to paddle Emerald Lake this summer. It is located just inside the BC border along Highway 1, maybe an hour west of Banff. Best paddle of the year so far and definitely one of my top 5 paddles ever.
You can rent canoes there (see picture below). If you bring your own boats, you can launch off a small beach about 200 feet west of the parking lot (keep walking past the bathrooms). The parking area also has pit toilets and picnic tables and is the trail head for a hike around the lake. There is also a lodge here (just across the bridge).
The lake itself is a beautiful glacial green and was dead calm when were there. This year Yoho and Banff have imposed some restrictions on private boats (self-check in and a 48-hour drying period between lakes) to control aquatic diseases and pests. Emerald is a part of this project and it is worth reading ahead of time so as to not be disappointed.
It took us about 90 minutes to paddle the shoreline (at a modest pace) and the lake was so pretty we did it twice, once each way.
Wildlife was a bit thin but we did have a nice time with two loons and a chick. The loons were pretty calm as long as we kept our distance.
The far end of the lake has a number of creeks dumping into it. The one below was small. Further to the east there is a larger creek with a silty delta. I managed to get about 40 or 50 feet up this creek (which is moving pretty fast) before the channel got too shallow to continue.
The lake started to get busy with other boaters by about 9 am. Every picture at Emerald looks like a magazine cover so I'll just let you scroll down.
On our way back, we stopped in at the natural bridge and then went into Field. Field is an old railway town and looks like a model train set up. We had ice cream at the Truffle pIds Bistro and Lodge.