Here is what I do when my pool is shut down or when I want to save my legs from the constant pounding of long, slow runs:

If you want, add more running, but make it different:

1) Add sprint workouts, intervals, agility drills and running leg/PT

Sprints

Warm up for at least 5:00 and stretch well before going full speed. Hamstrings are the first to go if not properly warmed up/stretched:

- 20m - 1/2 pace x 2
- 20m - full sprint x 3
- 40m - 3/4 pace x 2
- 40m - full sprint x 3
- 60m - full sprint x 5
- 80m - full sprint x 3
- 100m - full sprint x 3

(Rest = walk back to starting line)

Running - 4 Mile Track Work

Jog - 1 mile in your goal mile pace

Three sets of:

- Sprint -1/4 mile / rest 1:30   
- Jog - 1/4 mile in goal mile pace

Six sets of:

- Sprint - 1/8 mile rest 45 seconds
- Jog - 1/8 mile 1:00 in goal mile pace

Running and Leg PT

Repeat 3-5 times

- Run 5:00 at goal mile pace
- Squats - 1:00
- Lunges - 1:00
- Heel raises - 1:00
- Stretch - 1:00

2) Other non-impact aerobics - rowing, elliptical glider, biking, stationary bike...

Getting out in the fresh air on a bike and cycling can be a great workout for folks, but personally, I find that it is safer and just as entertaining to get on a LifeCycle type stationary bike in front of a television. A few of my favorite stationary bike routines are the LifeCycle Pyramid and the Bike / Leg PT Workout:

Bike Pyramid

Lifecycle: Manual mode - Start on Level 2 and increase resistance by 2 levels each minute until failure - then repeat in reverse order - should take 20-23 minutes. I also do this type of workout on the Elliptical Glider as well. Keep the RPMs at 80-100 and you will have a puddle under you when finished (sweat).

Bike / Leg PT

Repeat 5 times

- Bike - 5:00
- Squats - 1:00
- Lunges - 15/leg
- Abs of choice - 50

Each minute on bike should progress in intensity (rpms or resistance levels)

Every now and then I like to see what I can row 2000m in using an Ergometer.

The indoor rower comes in several varieties and there are even world online competitions that are pretty fun to get into if you are one who likes to compete at ANY level.  Rowing is one of the hardest cardio exercises there is and you can build toned legs, arms, back and abs just by rowing.

If you like variation in your cardio workouts, any or all of these workout ideas should help you until you get access to the pool again. Who knows you may also enjoy one of the new routines and add that to you workout for a while. Remember - fitness is not a destination but a journey. You have to go site-seeing every now and then.