From: Jennifer Cline
Sent: Fri Jun 05 12:19:59 2015
To: Fasth, Bill; Mark Strandberg
Cc: Jonathan Patrick; Jason Clifford; jehredt@cityofmolalla.com
Subject: RE: Irrigation startup at North Coleman
Importance: Normal
Attachments: appendix N-North Coleman(1).xlsx; Hi Mark, Jon and Jake took moisture block measurements today at Coleman's and found moister block readings at Section to be around 80% saturated. However, based on the current RWUP with the 85% efficiency, it is projected that we would likely only be able to irrigate for an 18-hour set with one of the Big Guns. However, In order to irrigate we need to be able to go for a 24-hour set to keep the line charged. If the sites dry up more by Monday or if we can get DEQ to accept Bill's proposal of the 75% efficiency update for the RWUP, we can surely irrigate Section 3 on Monday. Jennifer Cline, P.E. City of Molalla Public Works Director O: 503.759.0218 F: 503.829.3676 -----Original Message----- From: Fasth, Bill [mailto:bfasth@BrwnCald.com] Sent: Friday, June 05, 2015 9:58 AM To: Jason Clifford; jehredt@cityofmolalla.com Cc: 'Mark Strandberg'; 'Jennifer Cline'; jon patrick; Jonathan Patrick Subject: Irrigation startup at North Coleman Jason and Jake, Mark Strandberg called me yesterday and mentioned that the lagoons are getting full. This prompted me to look at the tables in Appendix N of the RWUP that can be used to calculate maximum allowable gross irrigation. An updated table for N. Coleman is attached. In the updated table, I decreased the irrigation efficiency from 85% down to 75%. I can justify this revision because the value of 85% used in the RWUP was very conservative. Given this update, reaching a moisture block reading of 80% will allow you to irrigate 1 inch of water at N. Coleman. As we discussed at the meeting at Coleman Ranch on 5/1, this rate translates to 4 hr sets with the hand lines and 12 hr sets with the big gun. At that meeting, we also talked about irrigation sections 3 and 4 being the first ones to likely dry out. I don't know if moisture blocks or piezometers are located in those sections but if not, we can probably talk about some other alternatives. For example, an auger boring can be dug down to three feet in either of those sections and allowed to fill with water overnight. If there is no groundwater in the hole the next morning, you should be good to go. After start-up, the fields must be monitored closely to assure no runoff. Also, regarding irrigating in Section 3 just north of Feyrer Park Rd, you will need a 50 foot setback from the roadside ditch. Let me know if you have any questions. I will be available over the weekend too. Bill Bill Fasth 6500 SW Macadam Avenue, Suite 200 Portland, Oregon 97239 bfasth@brwncald.com<mailto:bfasth@brwncald.com> Cell 541.602.9110 [Description: http://help.bc.com/BC_logo_2line_prple.gif]<http://www.brownandcaldwell.com/>
