Pond Boss Forums AERATION Should I aerate? Aeration for stone stream/pool - Central TX

Greetings, pond pros!
Here's my situation - I live just south of downtown Austin, TX and happen to own a lot that extends halfway across a spring-fed creek running through the hood. The creek is empties in a large bowl directly behind my house creating a sort of swimming hole for the locals kids and a fishing spot for some. It's roughly 50 ft in diameter ranging from ledges at 1-3 ft deep to a large channel down the middle at 8 ft.
At any rate, like most creeks around this part of the country, it's cut into limestone and is real perty when the water is flowin'- in fact, during some periods of consistent rain i've seen some pretty decent fish swimming about and can see about 6 ft deep.

During the summer months and periods of little rain, the whole thing can get a bit funky - a light film on the surface, murky - and the spring although constantly running, isn't creating enough motion or displacing enough water to get good oxygen flow. The other aspect is that a few culverts drain into this so any random gunk on the roads will wash in it- not to worried about consuming the water or anything living in it - just want to have a nice habitat for fish and other wildlife.

I'm considering adding an aeration system and am looking for advice. Any special considerations to take regarding it being a creek vs a pond, limestone vs whatever, urban runoff, city ordinances ;-)
the fact that our summers can easily have 100+ degree days for weeks on end and no rain.

Here is a video I took of the creek after a pretty heavy rain - http://www.youtube.com/watch?v=kUnicIvfsPQ

and here is a pic of it's normal state - (this shows about half of it (I know, bad pic)
http://picasaweb.google.com/lh/photo/bOiqOJgK8utk42BQ3FiLQe6oA-DpZt85AeUuGM6xyTo?feat=directlink

Whew! Thanks for listening...

Normally a stream or creek is moving enough that the DO does not get to dangerously low for fish. However part of all streams, rivers, or creeks "anatomy" is the pool area. The pool areas are slower moving and can be treated almost in the same way a pond is at least as far as wildlife is concerned. These pools will be inhabited by the same types of fish that a small pond would hold. An aeration system could be useful only for localized aeration when the water is becoming stagnant.

My firs two questions are do you own the property the pool is on? Is this a named creek by your city/county?
Also how close is electricity to the pool?

If you own the land and others are using it you have a potential liability problem.

Aeration will help oxidize urban pollutants such as hydrocarbons and will also help assimilate nutrients such as fertilizers, animal feces, lawn clippings, etc. so that they're less available for algae. Aeration also helps reduce levels of pathogens which could be important since these kids are swimming in what sounds like an urban stormwater retention pond that could very well have fecal matter and other nasties in it. However, an aeration system is really only necessary if you have low dissolved oxygen (DO) levels. So, my recommendation would be to test your water for DO before purchasing an aeration system.

First of all, thanks for the responses - this is really a great forum.

Yeah, it's a interesting situation - this was once all private land and then the owner of a large portion of it donated it to the city. So it became a 'pocket park' - technically owned/managed by the city, but is really only used by the folks that live w/in a couple blocks.
Regarding my liability, my property line runs about 10 ft out in the center of the creek/pool, but I'm almost certain that these urban streams are the city's domain. Which means technically I shouldn't be altering it any any way - especially in any way that would restrict water flow - but I feel this in no way restricts water flow or creates a hazard to anyone.

So, thanks for bearing with my rambling.

Sounds like first my first step should be to test the water for DO. And yes, any aeration system I get (if at all) would be used sporadically - mostly during the summer months and any periods of low precipitation.

So if it's determined that my DO levels are pretty low, what size/model/make aerator do you think would be sufficient. Again, this wouldn't be running 24/7/365 and it is part of a spring fed creek, so there is a certain amount of aeration going on at all times.

Oh, and electricity is pretty close - I would likely have to run about 20 ft of conduit and set up an outlet in my back yard.

I would be very careful about running anything electrical on land that is shared or owned any part by the city. If anything were to ever happen like a short/cut extension cord/short in equipment, they are coming after you. Why not see if Game and fish might lend a hand with state equipment or check with city and see if they might lend a hand. This would keep the legal liability off you hands and they could help save a nice creek. Just an idea.

Just found this thread, DavidP, and have to say with that kind of water, the heck with an aeration system - buy yourself a whitewater kayak oriented to pulling off whitewater rodeo tricks and go tear it up on that slide!