From: Ryan Hepler

Sent: Wed Nov 29 09:43:22 2017

To: Andy Peters

Cc: 'Gerald Fisher'

Subject: Intake screens

Importance: Normal

Attachments: intake screen.docx;

Andy,

This morning I air purged the Intake screens and the lower screen (the one that had ruptured underground that we repaired) now seems to be plugged. I assume that dirt and gravel made its way down the 3” pipe sometime after it was broken. I remember this happening last time this air line broke and at that time we had to dig up and remove a coupling at the screen. The air line reduces from 3” schedule 80 plastic pipe to 2” galvanized pipe at the bottom of the intake screen. If I had to guess, this is where the blockage is happening. The good news is that the upper screen is still working so I am hoping that this will get us through the winter season. Each screen is rated at 4mgd each, however they are buried by river rock now so that is reduced. I am thinking we will have to contract out this repair but that is something we can talk about. I am assuming this repair will have to happen during the in-water work period this summer unless it becomes and emergency. There is a chance the blockage could clear on its own and I will let you know if that happens. Let me know what you think. I attached a picture of the screen for reference.

Ryan Hepler | Water Treatment Operator

City of Molalla

117 N Molalla Ave. | PO Box 248 |Molalla, OR 97038

Office: 503.829.5408 I Fax: 503.829.3676

rhepler@cityofmolalla.com