20181097 Ver 1_RE External A question on MP revisions_20191028

Strickland, Bev
From: Haupt, Mac
Sent: Monday, October 28, 2019 1:33 PM
To: Katie Webber; Davis, Erin B
Cc: Steve Kichefski; Bradley Breslow; Benton Carroll; Tugwell, Todd J CIV USARMY CESAW
(US); Kim Browning
Subject: RE: [External] A question on Dogtown Mitigation Plan revisions
Katie,
After looking at your proposed changes and speaking with you on the phone I am ok with what you folks propose.
However, I will point out that it appears from station 1+75 to station 4+50 it appears the channel feature goes through
wetlands. If this is the case, and it may be related to an old pond bed (as Katie pointed out on the phone), we are
concerned that the feature will not maintain channel -like characteristics.
Sorry it took me awhile to get to this.
If you have any further questions or comments, give me a call or email.
Thanks,
Mac
From: Katie Webber [mailto:[e-mail]]
Sent: Tuesday, October 15, 2019 9:36 AM
To: Davis, Erin B <[e-mail]>; Haupt, Mac <[e-mail]>
Cc: Steve Kichefski <[e-mail]>; Bradley Breslow <[e-mail]>; Benton Carroll
<bca rrol I @ res. us>
Subject: [External] A question on Dogtown Mitigation Plan revisions
External email. Do not click links or open attachments unless you verify. Send all suspicious email as an attachment to
Good morning,
We are working on providing comment responses and a final mitigation plan on the Dogtown Stream Mitigation
Project, and we wanted to check in with you on one of the items before we submit.
You provided the following comment regarding DT2:
"Design sheet S5 shows reach DT2 as Enhancement 1. However, virtually no work is being performed except
for at the end of the reach. DWR suggest that this reach be a different ratio, and should likely be measuring
credit through valley length versus stream centerline since it appears no definitive stream channel may exist."
In response, we reviewed the DT2 design and generally agreed that a blanket Enhancement I crediting
approach was not justified. We decided to split DT2 into A and B reaches to allow for a more detailed crediting
approach. Reach DT2-A (Plan Sheet S5), will be the reach originally named DT2, and DT2-B (Plan Sheet S6)
will be the reach that originates in the power easement.

The work proposed in the upstream section of DT2-A is outside of the jurisdictional limits of the existing
stream, and the majority of proposed work in DT2-B will occur within an existing power line easement.
Therefore, no credit will be received for these areas despite the work we propose. To compensate for this
work, we are proposing to receive Enhancement II credit (2.5:1) for the length of the reach between the
upstream and downstream restoration areas on the DT2-A reach. We expect that the work proposed on the
headwaters of both reaches will reduce the sediment load in DT2-A bringing it closer to an equilibrium with
sediment transport capacity.
We are now claiming restoration on the downstream portion of DT2-A where we are plugging the diversion
channel and restoring flow through the valley into the existing pond bottom. This approach will improve the
sediment transport capacity of DT2-A which will promote stable channel dynamics upstream of the proposed
restoration.
Channel alignments through the enhancement sections of DT2-A and B were taken from surveyed thalweg
provided by a licensed surveyor. We anticipated this channel alignment to become increasingly defined once
reach sediment transport is restored. For these reasons we feel that the current alignment for the
enhancement sections is justified.
We have attached our proposed revised channel design for DT2 and would like it if you would review it in
advance of our resubmission. Please advise us if you consider this a balanced approach to this stream reach.
Thank you,
Katie Webber, LPSS, CPSS
Project Manager
RES I res.us
Direct: 540.905.4388 1 Cell: 410.279.5741