Plans for the greenway are now online

City Engineering has proposed three alternate plans for restoring the greenway, so citizens can be informed before the meeting scheduled for Monday, Nov. 30 at 6:30 pm, at Covenant Presbyterian Church.  Go here, and look for the link to Hillcrest/Upland on the top right.

The three options are:
  • Bury the stream and replace the sewer--apparently the original plan.
  • Leave stream on surface, but reinforce the bank with riprap, and replace the sewer.
  • Leave the streambank as is, with possible addition of three small metal rock dams ("vanes") at the upsgtream end to control erosion.  Sewer not replaced--only relined.
Impact of the plans on trees

Unanswered was whether work on the lateral sewage lines would require the cutting of any additional trees.  trees.    Options 1 and 2 say tree "clearing limits not shown in vicinity of laterals."  Chris Schmidt tells me that all the trees that need to be cut for lateral sewage lines are included in the X count. There are 21 lateral sewer lines, so it seems possible that additional trees might be cut.
  • Option 1 (buried stream) involves cutting down at least 55 living trees and 11 dead trees.
  • Option 2 (riprap open stream) involves cutting down at least 57 living trees and 11 dead trees.
  • Option 3 (leave stream mostly as is) involves cutting only 6 living trees and 1 dead tree.
My first look suggests we should back the third option--but I need to do more study.  Far fewer trees are cut with the third option, and the stream will look more natural.  Without riprap, water will  be visible more often.   I suspect Option 3 will save a lot of money--could some of the savings be applied to some plantings or terracing (stone walls to stop slumping in the steepest parts) ?

Update as of 11/29: I don't support any of the current options.  I'm closest to supporting Option 3, but it doesn't address the erosion.  We need more study, and a new option, Option 4.

I suspect that Option 2  will require larger equipment for both tree cutting and riprapping.   With Option 2, corners are cut so the stream becomes more straight.

Questions about the third option
  • What to the metal rock vanes (dams) do?  What do they look like? 
  • Would the vanes control all the erosion?  What about existing bank cuts?
  • Would any trees need to be cut for lateral sewage lines?  Update: Chris Schmidt says that trees that have to be cut for laterals are already included in the diagrams.
  • What size equipment is needed to repair the sewage line, and how would it get into the ravine?
  • Would any funds be included for terracing or naturescaping to restore damage that does occur
  • Has the sewer frozen so far?  If not, there's no reason to believe it will freeze in Option 3.

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