Bugs in the Water treatment plant

[looksatstars]

We have just built a small scale water treatment plant in one of our parks. 7000 gallon holding tank with chlorinator.
Everything is working fine but the bugs are really bad. I have never seen them flying around iin the plant but they are dead on the ground by the thousands. The plant is starting to smell as the operator is getting sick of cleaning the floor every day. We have a fan inside trying to get rid of some of the condensation but it is pretty humid in there. We are in the process of trying to seal up every hole but may be tough.
I'm thinking trying to change the enviornment inside the tank so the bugs may not find the plant so habitable. The operator says they are aphids but from experience in flyfishing, I am pretty sure the bugs are midges.
Anyone ever have this problem and dealt with it?

PS we have a similar plant, two kilometers away and no bug problem there but the storage tank is outside the building.

 

[cvg]

put up a bat nest and let them do the work

 

[ch81pc]

UV-insecto-cuter maybe? Better ventilation (forced air) directed acors the top of your tank should reduce your humidity and discourgae them, they like calm air so stiring things up a bit should make them go elsewhere.