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TABOR RIVERBANKPROJECT

STABILIZATIONPLAN

TABOR RIVERBANK STABILIZATION PROJECT PLAN

Snake River Encroachment Issue3 miles Below Tilden Bridge

BOOK 1

Contact lnformation: AuthorGlen Tabor208-7054475qlentabor@q.com649 S 1300wPingree, lD 83262

JOINT APPLICATION FOR PERMITS

U.S. ARMY CORPS OF ENGINEERS - IDAHO DEPARTMENT OF WATER RESOURCES.IDAHO DEPARTMENT OF LANDS

Authorities: The Department of Army Corps of Engineers (Corps), ldaho Department of Water Resources (IDWR), and ldaho Department of Lands (lDL) established a jointproreqs for activities impacting jurisdictional waterways that require review and/or approval of both the Corps and State of ldaho. Department of Army permits are required byS ) 10 of the Rivers & Harbors Act ot 1899 for any structure(s) or work in or affecting navigable waters of the United States and by Section 404 of the Clean Water Act forthe urscharge of dredged or fll materials into waters of the United States, induding adjacent wetlands. State permits are required under the State of ldaho, Stream ProtectionAct (Title 42, Chapler 38, ldaho Code and Lake Protection Act (Section 58, Chaptell3 et seq., ldaho Code). ln addition the information will be used to determine compliancewith Section 401 of the Clean Water Act by the appropriate State, Tribal or Federal entity.

lhe requested information may delay processing and issuance of the appropriate permit or authorization. Applicant rrrill need to send a completed application, along withone (1) set of legible, black and wfiite (8%"x11"), reproducible drawings that illustrate the location and character of the proposed project I activities to both theCorps and the State of ldaho.

See lnsfrucfion Guide lor assistance with Application. Accurate submission of requested information can prevent delays in reviewing and permitting your application.Drawings including vicinity maps, plan-view and section-view drawings must be submitted on 8-1/2 x 11 papers.

Do not start work until you have received all required permits froin'both the Corps and the State of ldaho

NWW $q. Ar_- W2USACE Date Received: -4\,4'I

5 Aq',0^ Za t 4f] lncomplete Application Retumed

Date Returned:

ldaho Department of Water Resources

No.

Date Received: I Fee Received

DATE:

Receipt No.:

ldaho Department of Lands

No.

Date Received: fl Fee Received

DATE:

Receipt No.;

INCOUPLETEAPPLICATIONS iIAY NOT BE PROCESSED

1. CONTACT INFORIIATION - APPLICANT Required: I z. conrncrNFoRMATroN-AGENT:

Name:

Glen and Bernadine TaborName:

Cnmpany:

n Springs Ranch, Inc.Company:

Mailing Address:

649 S 1300 WMailing Address:

City;

PingreeState:

IDZp Code:

83262

City: State: Zip Code:

Phone Number flio dude arca codo)i

(208) 70s-447s

E-mail:

glentabor@q.comPhone Number 6rdrde arean(k)i E-mail:

3. PROJECT NAME or TITLE: Tabor Riverbank Stabilization Project 4. PROJECT STREETADDRESS: 649 S 1300 w5. PROJECT COUNTY:

Bingham

6. PROJECTCITY:

Pingree

7. PROJECTZIPCODE:

83262

8. NEAREST WATERWAYMATERBODY:

Snake River

9. TAXPARCELID#:

RPOl506l3

10, LATITUDE:

LONGITUDE:

43.102137

-112.539633

11a. 114''

sw11b. 1!4:.

NE

11c. SECTION:

I1.1d. TOWNSHIP:

4S

11e. RANGE:

33E

12a. ESTIII4ATED START DATE:

Apr 1,2019

12b. ESTIIi/ATED END DATE:

Apr 1,2021

13a. lS PROJECT LOCATED WITHIN ESTABLISHEDTRIBAL RESERVATION BOUNDARIES?

I No I ves rribe:

13b. ISPRoJECTLoCATEDIN LISTEDESAAREA? E uo I ves I3c.TSPROJECTLOCATEDON/NEARH|STOR|CALS|TE? E UO f, yEs

14. DIRECTIONS TO PROJECT SITE: lnclude vicinity map with legible crossroads, street numbers, names, landmarks.

From Blackfoo! Idaho, drive south on US-91 5.5 miles to 500 SlFerry Butte Road. Turn west and continue 6.3 miles to Hilltop Road. Drive 1.1 mile to W600 Sfferry Butte Road and continue west to S 1300 WCaldwell Lane. Drive south 0.5 miles to the first unpaved road and turn east (left). The project islocated on the bank ofthe Snake River at the residence at the end ofthe road.

jA PURPOSEandNEED: l--l Commerciat [tnousridf] euOtc fi Rrivate I otner

,cribe the reason or purpose of your proyect; include a brief description of the overall project. Continue to Block 16 to detail each work activity and overall project.

The purpose ofthe project is to stabilize the riverbank and prevent further erosion ofthe soils to protect residential property and farmland.

FOR AGENCY USE ONLY

NWW Form 1 145-1/IDWR 3804-8 Page 1 of4

16. DETAILED DESCRIPTION OF EACH ACTIVITY WITHIN OVERALL PROJECT. Specifically indicate portions that take place within waters of the United States, induding wetlands: lndudedimensioos; equipment, construction, methods; erosion, sediment and turbidity controls; hydrological changes: general stream/surface water flows, estimated winter/summer flows; borrow

' sources, disposal locations etc.:

Pleuse refer to accompanying Tabor Riverbank Stabilization Project Plan.

17. DESCRIBE ALTERNATIVES CONSIDERED to AVOID or MEASURES TAKEN to MINIMIZE and/ or COMPENSATE for IMPACTS to WATERS of the UNITED STATES, INCLUDINGWETLANDS: See lnstructioo Guide for specific details.

The proposed project is expected to involve minimal impact to the Snake River. No wetlands are located within the project area. All work will be conducted

from top-of-riverbank or top-of-fill and resulting sloped bank; no equipment will work within the river channel. Except for excavator, rubber-tired

equipment will be used to minimize disturbance of existing vegetation atop the bank. Work will be conducted during the low water season.

18. PROPOSED MITIGATION STATEMENT or PLAN: If you believe a mitigation plan is not needed, provide a statement and your reasoning why a mitigation plan is NOT required. Or, attach a copy of your proposed mitigation plan.

A mitigation plan is not needed for this project as it consists of placement of fill material that will contain no fines, eliminating water quality alterations. Disturbance of the riverbed will be kept minimal and the channel will be reinforced but not redirected. The work will have little effect on the aquatic

resources of the river channel, as it will be confined to the riverbank and will be conducted during low river stage.

19. TYPE and QUANTITY of MA TERIAL(S) to be discharged below the ordinary high watermark and/or wetlands:

Dirt or Topsoil:

Dredged Material:

Clean Sand:

Clay:

Gravel, Rock, or Stone:

Concrete:

J (describe): _______ _

Other (describe: ______ _

___ cubic yards

___ cubic yards

cubic yards

___ cubic yards

2120 cubic yards

cubic yards

cubic yards ___

cubic yards

TOTAL: ,_-----------'2120 cubic yards

NWW Form 1145-1/IDWR 3804-B

20. TYPE and QUANTITY of impacts to waters of the United States, including wetlands:

Filling: acres sq ft ___ cubic yards

Backfill & Bedding: acres sq ft ___ cubic yards

Land Clearing: acres sq ft ___ cubic yards

Dredging: acres sq ft ___ cubic yards

Flooding: acres sq ft ___ cubic yards

Excavation: acres sq ft. ___ cubic yards

Draining: acres sq ft. ___ cubic yards

Other: acres sq ft. ___ cubic yards

TOTALS: acres sq ft. ___ cubic yards

Page2 of4

21. HAVE ANY WORK ACTIVITIES STARTED ON THIS PROJECT? l&J NO 0 YES If yes, describe ALL work that has occurred including dates.

22. LIST ALL PREVIOUSLY ISSUED PERMIT AUTHORIZATIONS:

NA

23. D YES, Alteration(s) are located on Public Trust Lands, Administered by Idaho Department of Lands

24. SIZE AND FLOW CAPACITY OF BRIDGE/CULVERT and DRAINAGE AREA SERVED: Square Miles

25. IS PROJECT LOCATED IN A MAPPED FLOODWAY? □ NO l&J YES If yes, contact the floodplain administrator in the local government jsrisdiction in which the project is located. A Floodplain Development permit and a No-rise Certification may be required. 26a WATER QUALITY CERTIFICATION: Pursuant to the Clean Water Act, anyone who wishes to discharge dredge or fill material into the waters of the United States, either on private or public property, must obtain a Section 401 Water Quality Certification (WQC) from the appropriate water quality certifying government entity. See lastruction Gulde for furlher clarification and all contact ihtormaffon.

The following information is requested by IDEQ and/or EPA concerning the proposed impacts to water quality and anti-degradation:

�NO

� YES Is applicant willing to assume that the affected waterbody is high quality?

NO YES Does applicant have water quality data relevant to determining whether the affected waterbody is high quality or not? NO YES Is the applicant willing to collect the data needed to determine whether the affected waterbody is high quality or not?

26b. BEST MANAGEMENT PRACTICTES (BMP's): List the Best Management Practices and describe these practices that you will use to minimize impacts on water quality and anti-degradation of water quality. All feasible alternatives should be considered - treatment or otherwise. Select an alternative which will minimize degrading water quality

Fill material containing no fines will be used for the project. Equipment used will limit disturbance to existing vegetation.

-

Through the 401 Certification process, water quality certification will stipulate minimum management practices needed to prevent degradation. 27. LIST EACH IMPACT to stream, river, lake, reservoir, including shoreline: Attach site map with each impact location.

Activity Name of Water Body Intermittent Description of Impact Impact Length Perennial and Dimensions Linear Feet

Riprap-barb placement Snake River Perennial Reinforce riverbank with riprap-barbs 1765

TOTAL STREAM IMPACTS (Linear Feet): 1765

28. LIST EACH WETLAND IMPACT include mechanized clearing, fill excavation, flood, drainage, etc. Attach site map with each impact location.

Wetland Type: Distance to Description of Impact Impact Length Activity Emergent, Forested, Scrub/Shrub Water Body Purpose: road crossing, compound, culvert, etc. (acres, square ft

flinp_arfl\ linc�rfl N• No wetlands in project area. NA NA 0

TOTAL WETLAND IMPACTS (Square Feet): o

NWW Form 1145-1 /IDWR 3804-B Page 3 of 4

29. ADJACENT PROPERW OWNERS NOTIFICATION REQUIREM: Provide contact information of ALL adjacent property owners belou

Name:

Van Orden Brothers Lan{ LLC (Gaylen Van Orden)

," 1nS

Address:

JW600S

City: State:

Pingree

Phone Number iin dude ffia code)i

(208) 68r-4e01

IDZp Code:

83262

E-mail:

farm ingmanS6@hotmail. com

Mailing Address;

Phone Number pn &rds aM mda):

Name:

City:

E-mail:

State: Zip Code:

Name:

Outland, LLC (Glum Foreman)

Mailing Address:

216 Heppler Lane

City:

Saratoga SpringsState:

UTZp Code:

84045

E-mail:

glennf@mudbuddy.com

Ph one N Umbef f,ir, &tde area code)i

(801) 352-801 l

Mailing Address:

Phone Number 6n drde aea ffi{k)i

Name:

City:

E-mail:

State: Zp Code:

Mailing Address:

Phone Number ptr tude arca @tu)i

Name:

City:

E-mail:

State: Zip Code:

Name:

Bureau of Land Management, Idaho Falls District

Mailing Address:

1405 HolliparkDrive

City: State:

Idaho Falls ID

Mailing Address:

Phone N umber f,io dtda rea mde;.

E-mail:

City:

E-mail:

State: Zp Code:

Zip Code:

83401

Phone Number til d)de arca mde):

208-524-7500

Mailing Address:

Phone Number pirdr& aM cado):

Name;

City:

E-mail:

State: Zip Code:

30. SIGNATURES: STATEMENT OF AUTHORIAZATION / CERTIFICATION OF AGENT / ACCESSApplication is hereby made for permit, or permits, to authodze the work descnbed in this application and all supporting documentation. I cefttfy that theinformation in this application is complete and accurate. I further ceftify fhaf I possess the authority to undeftake the work desaihed herein; or am actingas the duly authorized agent of the applicant (Block 2). I hereby grant the agencies to which this application is made, the ight to access/come upon theabove-descibed location(s) to inspectthe proposed and completed worUactivities.

Signature of Applicant: Date: 3- t-t?

Signature of Agent: Date:

-his application must be signed by the person who desires to undertake the proposed activity AND signed by a duly authorized agent (see Block 1, 2,

.,1. Furlher, 1 I USC Section 1001 provides lhal 'Whoever, in any manner within the juisdiction of any depaftment of the Unrfed Sfafes knowingty and

willfully falsffies, conceals, or covers up any trick, scheme, or dlsgulses a mateial fact or makes any false, fictitious, or fraudulent statements or

representations or makes or uses any false witing or document knowing same to contain any false, fictitious or fraudulent sfafemenfs or entry, shall be

fined not more than $10,000 or impisoned not morc than fwe years or both'.

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Tabor Riverbank Stabilization projectSnake RiverBingham County, ldahoGlen and Bernadine TaborJanuary 3,2019

36Pingree

Site of Proposed

Riverbank Stabilization

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SNAKE RIVER ENCROACHMENT:TABOR RIVERBANK STABILIZATION PROJECT PLAN

SYNOPSIS:For many years, the Snake River has been slowly moving towards and into the Foreman and Taborproperties. Recently, its encroachment has accelerated and has now placed two expensive structures inimminent danger. We need immediate help to save these two structures and then help to permanentlystabilize the Snake River. The current situation is that the north/west bank is almost vertical and about10 feet above the OHWM. During the recent high flow periods, the HWM is at the top of this bank andthis massive hydraulic force is eating away the bank at arate of 50 to 60 feet per year. The river is nowabout 40 feet from the Foreman shop (structure 1) and about 60 feet away from the Tabor dam (structure2). This application and plan address both the immediate and permanent issues.

SECTION I . DESCRIPTION OF ISSUE:

BACKGROUND:The subject project site is situated along the north/west bank of the Snake river along an unusual o'fish

hook" shaped channel path; see Project Vicinity Map and Project Site Location images, pages la & Ib.

The Snake River is known for its natural channel meandering. Fortunately, much of the land involved inits channel movement is unimproved or rural land. Occasionally, however the Snake River encroachesinto high value land/property and creates a serious issue that must be addressed. This project is such acase.

In addition to the natural forces that cause the Snake's meandering, man-made factors have alsocontributed to the Snake River channel instability as it applies to this project. The 1974 the Teton Damdisaster affected the subject site. Anecdotal evidence confirms that the resulting flood covered thesubject site fields east of the creek and the creek itself for several days. It is believed that this floodingcreated or etched deeper an existing shallow furrow such that the bottom of this latent channel washigher than the ordinary HWM but lower than extraordinary spring runoff HWM as shown in the LatentChannel image on page lc. Then, during the years when the river is running high and fast, this latentchannel began redirecting the river further north and the hydraulic forces continued to deepen this ditchuntil it become the main channel. This allowed the river to flank the otherwise stabilizing riparian landthat was a natural barrier to bank erosion and continue its encroachment eventually wiping out thisriparian buffer.

A more recent contribution to this site's bank encroachment has been the negative effects of cattle. Forthe past several years, cattle have swum the Snake River from the Shoshone-Bannock Reservationgrazing allotments as they are pushed north during fall round-up. 2018 was particularly bad in thatseveral occuffences of 40 or more head attempting to climb the -1O-foot vertical banks (onto the Taborcrop field and along the Foreman bank) cut deep crevices from below the water surface to the top of thebank. Shortly thereafter, sections of bank were seen crumbing and calving off. One group successfully

Page 1 of16 @ 2019 Glen Tabor All Rights Reserved

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Tabor Riverbank Stabilization projectSnake RiverBingham County, ldahoGlen and Bernadine TaborJanuary 3, ZOL}

Page 1a

PROJECT SITE LOCATIONTabnr Riverbank Stailization project

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,i, 20'19 Glen Tabor All Rtghts Rese rved

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.- \ ciimbed the downstream side of the creek dam, destroying the riprap that had been shielding the dam (it' has now been repaired).

Perhaps the most on-going man-made influence has been the Bureau of Reclamation's control of SnakeRiver flows. This is not a statement of blame but merely recognition that increasing water volumes bythousands of cubic feet per minute (especially during spring runoff and flood control measures) in ashort period of time in this site's unusual fish hook channel path is now causing losses in excess of 50feet per year of bank encroachment. Of course, the alternative is no flood control and accept whateverdamages might result. The amount of encroachment is detailed below.

ENCROACHMENT:Based on aerial photggraphs from USGS, satellite images from Google Earth, field inspections andanecdotal referencesl a composite of the subject channel migration has been formed. Fl"ur" refer toimage entitled 1992-2018 Encroachment Progression onpage 3a and TABLE 1: RATE OFENCROACHMENT, below. The composite image on page 3a was derived from the ten satellite images1992'06 [/SGS through 2017-06 USG,S found in APPENDIX l. They were obtained using GoogleEarth Pro software.

These are geo-referenced images such that the stable items appear in the same place on each image. Theannual positions of the North, then West bank of the Snake River in the "fish hook" areacan be trackedusing these images.

TABLE {: RATE OF ENCROACHMENTPeriod,vears

Number of years perperiod, years

Encroachment,feet

Rate of Encroachment,feet per vear

1950-19921 42 200 5 feet per year1992-2003 ll 240 22 feet per year2003-2004 1 10 10 feet per year2004-2006 2 t6 8 feet per year2006-2009 a

J 44 15 feet per year2009-2011 2 t4t 7I feetper year20tt-2013 2 25 13 feet per year2013-2014 I 43 43 feet per year2014-2016 2 29 15 feet per year2016-2017 I 65 65 feet per year2017-2018 1 54 54 feet per year

Total 1992 throueh 2018 867 33 feet per year

The image, 1992-2018 Encroachment Progressiaz, shows the spread of encroachment in relation to thetwo subject threatened properties. The base satellite image shown in this composite was taken in June of

t Especially from Bernadine Tabor who as an infant moved onto the original Smith ranch that contained the two subjectproperties and clearly recalls the river channel from the 1950's while she resided on and helped farm this property.

Page 2 Of 16 @ 2019 Gten Tabor A[ Rights Reserved

,.\ 2017. The current boundaries of the two subject properties are shown by the red (Tabor) and orange/ (Foreman) polygons. The earthen dam is highlighted in this image and identifies the spring-fed creekflowing south in front of the Tabor house. It is used as a point of reference for several measurements.Three data tracks of the north/west bank of the Snake are shown. Each track shows the sameapproximate spot on the bank for each satellite image year seen in the ten above referenced images.(The 2018 track points are from actual field observations as no satellite images were available for 2018).

There is nothing to suggest that this encroachment will not continue unabated unlessstabilization/mitigation actions are taken in the immediate future.

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--) Page 3 of 16 @ 2019 Glen Tabor All Rights Reserved

River EncroachmentTabor Riverbank Stabilization project

RIVER ENCRCACHh{ENT 1gg2 THROUGH 201B

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1 -\ SECTION ll - ANALYSIS OF LOSSES AND THREATS:

The two subject properties include irrigated farm land, a spring-fed creek that forms an important naturalfish habitat that flows into the Snake Rivero and the residences. The Glenn and Connie Foremanresidence includes their home, a modern steel-constructed shop, some outbuildings and approximately 5acres. The Glen and Bernadine Tabor residence includes their home, a modem steel-constructed barn, amodem steel-constructed shop, several outbuildings and about 16 acres. Note that the site in 1992consisted of about 33 acres. Of critical importance is a spring-fed creek that runs through the Taborproperty behind an earthen dam and empties into the Snake River. This creek provides a valuable fishhabitat for Rainbow, German Brown, Cutthroat and Cut-bow trout. It also supports Blue Heron, BaldEagle, Osprey, a pair of beavers, muskrat and raccoons. Sand Hill Cranes use this property as apermanent layover during their annual migrations. This creek provides year-around habitat for Canadageese, several species of duck and a resting place for them from the pressures of hunting. The creek iswhat makes this property unique and highly valuable.

Nine photos illustrate the losses and threats to the subject properties. They are labeled P-l through P-9(pages 5b through 5g). To help clarift where each photo was taken, a Guide to Loss/Threat Photos isprovided on page 5a.

LOSSES:Loss: 17 Acres:From 1992 to 2017, the Snake river eroded (obliterated) approximately 15 acres of crop/pastureand riparian site land. The Cottonwood trees, brush, berries and plants growing on the riparianpart provided habitat for white-tail deer, etc., before they were lost. In 2018 another estimated 2acres was lost (see the earlier encroachment images).

Loss : Penins ula obliteratedIn addition to the loss of the -17 acres the other key loss has been a critical barrier for theForeman property.P-l: (page 5b) shows a strip of land jutting south from the dam and on the east side of theForeman property was known as the peninsula. This photo shows the peninsula as it was in2013. In the spring of 2018, the river destroyed this peninsula. It was a primary protection forthe Foreman residence against the river. As it now stands, the full force of the river is directedinto the Foreman residence.P-2: (page Sc-upper) shows remnants of the peninsula as it is now.P-3: (page 5c-lower) shows the peninsula stub from the river side.

THREATS:Threat: Loss of Dam & Creek ViewsP-4: (page 5d-upper) shows the spring-fed creek looking north from the dam. This dam is whatmakes the creek. It has created the creek habitat enjoyed today and is in imminent danger. It isalso the only means of ingress/egress onto the east crop/pasture field. The loss of the dam meansthe loss of creek.

Page 4 of 16 @ 2019 Glen Tabor All Rights Reserved

P-5: (page 5dJower) shows the river within about 60 feet of this dam in 2018. The cover photoson the face of the 3-ring binder shows the river's encroachment in the o'flood" of 2018.

Threat to Tabor HouseP-6: (page 5e). This photo taken in February of 2019 shows how the river bank is calving off asthe river continues its relentless encroachment west and north.

Threat to Foreman Shop (and House)P-7: (page 5f). The tan building in this photo is the Foreman shop. The most serious threat isnot shornrn in this view. The brush along the Snake's bank on the right side of the image hides agulley that during high and fast river flow allows the river to chew up the bank next to this shopatanalarming rate.P-8 (page 5g-upper) shows the west bank of the Snake River and the inlet of the gulley and theshop.P-9 (page 5g-lower) shows the gulley. Foreman estimates the west side of this gulley to be -40feet from his shop.

The imminent threat of continued Snake River encroachment into the two subject residential propertiesis that the Snake River will continue to move unimpeded north and west until it takes the land, buildingsand infrastructure that make up these residences. It is eating its way north and west at 50 to 60 feet peryear in high flow years. Unfortunately, the soil between the current Snake River channel and theseproperties is mainly gravel with approximately 12 inches of overburden or top soil. There are a fewfingers of lave rock outcroppings that provide precious little resistance and have proven ineffectiveagainst the hydraulic force of this river. Left unabated, it is very likely that the river will continue tomove west and north, consuming everything in its path. It is likely that within one to two years, theSnake will destroy the dam and then the creek and take the X'oreman shop. Besides the tremendousloss in property value that will result, loss of this precious creek habitat is unconscionable. This projectis designed to stop the continued encroachment and stabilize the bank.

Page 5 of 16 @ 2019 Glen Tabor All Rights Reserved

P-1

12-15-2013 From Dam Looking SE

F PENINSULA: From Dam LookingsE

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\ SECTION III - PROPOSED SOLUTION:

PROJECT STABILIZATION PLAN:The project plan contains four inter-related remedies: (1) Sloping indicated sections of river bank andarmoring with riprap, (2) Adding biomass in the form of planting willows on the slopes, installing bio-bundles where practical and re-introducing cottonwood trees along the top border, (3) Constructing bendweirs (i.e., stream barbs) strategically placed in several places along the subject bank and repairing a 50'x 100' portion of the peninsula and (a) Taking Emergency action for two critical threatened areas.

This plan is anticipated to require multiple years for completion. The general approach follows thedesign approach of USDA/It{RCS Technical Notes: Engineering-No. 12, Design of Stream Barbs. Itisconsistent with the recommendations of consultants who have examined this situation.

This project encompasses stream barbs to redirect the current Snake River flow inward back to thesouth/east to stop the encroachment into both subject properties. It relies on riprap and plantedvegetation on sloped banks in concert with the stream barbs to provide long term bank stabilization. Itwill be sensitive to environmental requirements and will adopt necessary bioengineering practices toinsure clean waters. Please refer to the Project Detail Overview image on page 6aandthe Barb SiteOverviews image in Appendix 2.

1. STREAM BARB DESIGN:These stream barbs are designed to function as bend weirs. This plan consists of four barbs placed alongthe Snake's north bank on the Tabor property (See Barb A through D Views images in Appendix 2.)and recognizes that at least one barb should be placed on the west bank on the Foreman property, subjectto Foreman's approval. The specific location of this barb is dependent upon the efficacies of barbs A-Dand will be field located. Please refer to the three drawings which detail the barb and bank designfeatures:

Barb ond Bank Construction Plan View, (page 13a)Barb and Bank Cross-Section, (page 13b)Chunnel Design ProJile (page l3c)

The approximate location of the stream barbs is shown the Project Detail Overview image on page 6a.The reference point for the measurements is the dam culvert (43" 6.247'N, I l2o 32.330'W: 4405 ftMSL). These locations may change a little to accommodate the actual bank condition at the time ofconstruction. This satellite image was taken in June of 2017 and does not represent the actual conditionas of February 2019. There are two important changes worth further comment. First, the northwestriverbank moved an additional average of 54 feet due to the continued erosion experienced in 2018(portrayed by the green polygon). Current position of the bank is shown (approximately) by the red andwhite lines. Second, the June 2017 base satellite image of this overview shows the Snake at its fullestheight and therefore its fullest width. This width is greater than the channel-forming width as the riverdepth near the south bank is very shallow with low water velocity and would be better described asflooding, not channel cutting. The Peninsula re-build is treated as a barb that extends above the HWM.

Page 6 of 16 O 2019 Glen Tabor All Rights Reserved

PROJECT DETAI L OVERVI EWTabor Riverbank Stabitization project

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IMPORTANT METRICS:See Appendix 3 for a list of Critical Parameter Values developed in this section.

OHWM = Ordinary High-Water Mark = -10 feet below the natural top of the north bankIn this project area

D : The depth of stream flowBecause the river bed profile is far from uniform (See Drawing: Channel Design ProJilepage 13c), the average channel-forming depth, Dcrwill be used for D.

Dcr E Average Channel-forming Flow Depth:This metric is difficult because the Snake River water surface elevation increases from --2 feet below the OHWM during dry-year low flows to +10 feet above the OHWMduring spring runoff in high-stream flow years.Dmin: 8 ftDmax = 20 ft

Dcr = 10 ft at OHWM

w = Specific weight of water = 62.4lbs/cu.ft.

S" = Channel GradientTo determine the local stream gradien! elevation data was collected from severalsources within the project area and over both short and long distances above andbelow the project. The three gradient calculations were very consistent:

Sc : Average gradient is 0.00123 or L.23 ft drop per 1,000 ft length

Sn = Slope of Constructed Bank =2H:lY = 26.6

CR = Radius of Curvature of North Bank of river between Barbs A & D = 560 ft

WSW = Water Surface WidthAt Minimum flow : L97 ft.At Maximum Flow = 238 feet

WSW: WIDTH OF RIVER PERPENDICULAR TO BARB LOGATIONBARB LOCATION At Hishest IIWM FEBRUARY 2OI9*A 250 feet 180 feetB 233 feet 200 feetC 220 feet 210 feetD 250 feet NRAverage 238 feet 197 feet

*Rangefinder measurements taken on February 16,2019 when the Snake was near itsOrdinary High-Water Mark.

PageT of16 @ 2019 Glen Tabor All Rights Reserved

Wt = Total Channel-forming FlowWidth = 100 ftWeff E Effective Channel-forming FIowWidth = 40 ft

C : Stream Curvature Coefficient: based on Table, below.

Stream Curvature CoefficientC CR/WSW:

0.4 extrapolated 2to 40.6 4to 6

0.75 6to 90.90 9to121.00 Straieht Channel

(CR/WSW)min flow, Stream Curvature Coefficient = 560 ft ll97 =2.84: C,nio 3 0.4(CR/WSW)max flow, Stream Culature Coefficient = 560 ft 1238 = 2.35: C'"* 3 0.4

K = Bank Slope Coeflicient for bank slope of 2.00:1 = 0.72

BARB AIYGLE, O:Vector analysis suggests that an angle of 30o from the tangent of the stream bank will be mostefficient and will follow generally accepted guideline of 20 to 45o limits.

O, Barb Angle = 30"

BARB LENGTH, L:The actual barb length, L, is a function of the eflective barb length, Len which is a function ofthe barb angle, 0. Engineering standards suggest that the effective length, Len of the projectbarbs should not exceed 25Yo of the channel-forming flow width, W. The effective length is theperpendicular projection from the stream bank.

Len , Effective Barb Length : % (100) = 25 ft.

The actual barb length is found by the trig relationship: sin(O) = Len/ L.L, Actual Barb Length =Ler f sin(0) = 25/0.50 = 50 ft

BARB SPACING:Based on the bank geometry, engineering considerations and hydrological findings that a bendweir influences the downstream flow directions for 5 to 10 times its eflective length, a vectoranalysis with iterations suggests for the 850-foot long bank along the Tabor pasture, four barbsspaced at approximately 250 ft is appropriate.

BARB HEIGHT, hnax:It is recommended that the barb top slope slightly (no more than a l0-degree slope) from thebank to the instream end. The maximum height of the SO-foot barb at its midpoint length is

Page 8 of 16 @ 2019 Glen TaborAlt Rights Reserved

recommended in Technical Engineering Note 12 as, h**: 0.33D"rto 0.50D"r: 3.3 ft to 5.0 ft.where the Dcrfor the ordinary high-water mark will be used (i.e., D"1: l0 ft).

However, for this application a slightly higher barb height will provide slightly higher flowforced over the barb. The hydraulic analysis (see below paragraph, HYDRAULICS) suggeststhataminimum barb height should be 6 feet, based on the average channel-forming flow depth,Dcrof 10 feet. Which is20Yo higher than the suggested barb height referenced above.

h'"*, Barb HeighF 6.0 ft.

BARB ROCK SIZE GRADATION:The barb rock size is determined from modiSing the riprap rock gradation sizes calculated inIdaho Technical Note 6 for material placed on the stream bed as shown in the table below.

The riprap DTsriprup rock size is calculated using the method found in the Idaho Technical Note #6AS:

Dzs.tp.ap = 2.5(wD.rS"l C')Dzs rip*p : (2.5*62.4*20*0.00123)10.4:9.6" = l0 inches

The remaining gradation sizes are determined by the following relationships:

EQUATION:STREAM BED RIPRAP ROCK GRADATION

VALUES:STREAM BED RIPRAP ROCK GRADATTON VALUESRock Size Minimum Size Maximum SizeDloorior- 1.33 x 10": 13" 2.00 x 10" :20"D75.io*o 1.00 x 10": 10" 1.67 x I0" :17"D5o.ioruo 0.67 x 10" :7" l.l7 xl0":12"D25.io*o 0.33 X 10":3" 0.77 x 10":8"Do rioruo none 0.33 x 10": 3"

Converting the riprap rock sizes into barb rock sizes uses the conversion method found in theEngineering Technical Note 12:The working Barb rock size values will be the average between the minimum and maximumvalues per the cited method.

I)sorarb , Barb Rock Size = 2 x9.5 inches = 19 inchesPage 9 of 16

Rock Size Minimum Size Maximum SizeDloorinr- 1.33 x D75.ioruo 2.00 x D75.ioruo

DT5 rinon 1.00 x Dzs .io*o 1.67 xD75.io*oD5o.inrrn 0.67 x Dz5 rioruo 1.17 x D7s ,io*oD25.in.un 0.33 X DTs.ioruo 0.77 x DTs.inrup

Do riorun none 0.33 x DTs rioruo

@ 2019 Glen Tabor All Rights Reserved

From the Engineering Technical Note 12 method the remaining rock gradation sizes specified can befound from the stated equations:

Barb Rock Size Droor*n : 2 x Dsob*u :2 x 19: 38 inches.Barb Rock Size D*inu*r : 0.75 x D50.iprap : 0.75 x 9.5 : 7 inches

DESIGN BARB ROCK GRADATION TABLERock Grade Design Size

Diameter, inchesDloobu.b 38 inchesDzs t*u l9 inchesDsourn 14 inchesDminbarb 7 inches

BARB WIDTH:It is recommended that the barb width be 2 to 3 times the maximum barb rock diameter, Droobaru

Barb Width can now be calculated as 2 x Drool*r :2x38" :76" inches (-6 Yrft)

Wbarb ' BARB WIDTH = 76"

(However, it may be necessary to make some of the barb wide enough to supportplacement equipment. 3 x 38" : ll4 inches may be more practical.)

BANK KEY:It is likely that the river flow will attempt to flank each barb and create erosion behind the barbTo prevent this a bank key will be constructed as an extension of each barb. The bank key willuse the same material and sizes as the barb. The key will be cut into the bank up toapproximately 8 feet and will rise to the top of the bank as the Snake frequently reaches near tothe top and in some places actually tops the bank. Its construction will mimic the barb's.

Lr , Bank Key Length= 8 ft.

BED KEY DEPTH, DI:A bed key will be placed at the end of each barb as required. It will be placed into the bed at arecommended depth of Drooriprup: 20 inches.

Dr, Bed Key Depth= 20 inches

HYDRAULICS:Three important parameters are addressed in the hydraulic analysis. First is the ratio of flowover the barb to total flow. Second is the Froude number which relates to whether the force ofthe hydraulic jump is suffrcient to redirect stream flow and third is whether the weir (barb) heightabove the stream bed is effective as indicated by the height of flow over the barb (assuming abroad crested weir configuration).

BARB F'LOW, Qbarn:

Page 10 of16 @ 2019 Glen Tabor All Rights Reserved

Quaru = Channel forming Flow over barb, cflsQtotur = Total channel forming flow, cfls: 5,000 cfls (typical non-extreme flow)Abarb r Channel Area the Barb Impacts, sqft : h x Leff: 6 x25 : 150 sqftAtot'r E Total Channel Area, sqft: Dcrx'W"ff: 10 x 40:400 sqftQu*t: (Aut / Atotzt ) x Qtotut : (150 I 400) x 5,000: 1875 cf/s

(1) Qr".u / Qtot"l, Barb Flow Rafio = 0.375Note: The NRCS Technical Notes Engineering #12 requires Qu*r I Qtotur > 0.1

FROUDE NUMBER, FT:Fr = In general this is a dimensionless number that is the ratio of inertial and gravitationalforces. In this application it is expressed as:

Fr: (Qu*r) / [(L x y2) x (g x y2)0'5] , whereL: total length of barb:50 ftyz : shallowest depth of water flow over barb : (Dcr- h) I 2:2 ftg : gravitational constant :32.2 fls2

Fr: 1875 / [ (50 x2) x (32.2x2;os t : 1875 / 803(2) Fr, Froude Number =2.34

Note: The NRCS Technical Notes Engineering#|2 requires a Froude number of greater thanl.Tand prefers a value of 2.5 or higher.

HEAD OVER WEIR, H:The height of the water flowing over the barb when added to the barb height, h, should be limitedsuch that this sum is not greater than about 120% of D"r, the depth of the channel forming flow(i.e., H + h < 1.2 x Dcr < 12 ft).H: [Qu*r / (C x L)f'aotNote: The equation shown in the NRCS Technical Notes, Engineering#12 is incorrect.

C is a discharge coefficient for broad crested weirs and varies fuom2.3 to 3.3 dependingupon the breadth of the weir crest and H. The referenced note #12 suggests using 2.8.

H, Head over Weir: [1875 I (2.8x 50;10'002: [3.39]0667 = 5.6 ft(3) H +h = 5.6 * 6 = 11.6 ft which is less than12 ft.

The implication is that the designed barb should not produce excessive baclarater effects.

2. BANK SLOPE DESIGN:The banks indicated in this project will be constructed using standard riprap armoring on constructedsloped banks. Please refer to the three drawings: Barb and Bank Construction Plan View, Barb andBank Cross-Section, and Channel Design ProJile (pages l3a,b, and c).

SLOPE, Sn:

All project river banks will be sloped with a 2H:1V slope (26.6o) where ever possible.

Page 11 of16 @ 2019 Glen Tabor All Rights Reserved

- -\ Sn, Slope of Constructed Bank = 2H:1V = 26.6"

BANK SLOPE RIPRAP ROCK SIZE:NRCS Technical Notes Engineering No. 12 recommends using Idaho Technical Note 6 methodsfor determining the size and gradation for the nprap that is to be placed on the bank slope.Following a similar approach shown above for frnding the stream bed rock sizes used in the barb,the D75;p6p size is frst calculated by a slightly different equation:

Dzs .iprup : 3.5(wDcrS " I KC'), inches

Dzs 'ip'up

: (3.5 x 62.4 x l0 x 0.00123) I (0.72) x (0.a) inchesDls

'ip*p :9-375 inches

NRCS Technical Notes Engineering No. 12 uses the following table as a guide for proper riprapgradation. To this table a 25Yo safety factor will be added to the Maximum Size column and beused to determine the Design Gradation.

REF. BAI\K SLOPE RIPRAP ROCK GRADATION TABLERock Size Minimum Size Maximum SizeDloorio.- 1.33 x 9":12" 2.00 x 9": 18"D75.ioruo 1.00x9"-9') 1.67 x9":15"D5o rioruo 0.67 x9":6" l.l7 x9": ll"D25 rio.o 0.33X9)'*3') 0.77 x9":7"Do.io.uo none 0.33 x 9" :3"

The bank slope will be covered with a gradation of rock sizes as shown in the Table, DesignBank Slope Riprap Gradation Table, shown below.

DESIGN BANK SLOPE RIPRAP GRADATION TABLERock Grade Design Size

Diameter, inchesDroorior- 23 inchesDTs rio*o 19 inchesD5o.io*o 14 inchesD25 .in.r., 9 inchesDo rinr- 4 inches

Dzs.ip."p , Bank Slope Rock Size, : 19 inches

3. BIOMASS DESIGN:Willows are some of the most successful plants to stabilize stream banks and will be used in this project.Willow cuts and root bundles will be mined into the bank (- I per l0 ft2). Once the banks havestabilized sufficiently, Cottonwood trees will be introduced along the top of the banks as will othervegetation forms that will support the re-habitation of current plant and animal life, especially thoseendangered species that are recommended by pertinent organizations.

Page 12 of l6 @ 2019 Glen Tabor All Rights Reserved

/''-\ Two types of willow planting are anticipated. A large number of "pongee" sticks (small limbs cut from' nearby active willows) will be planted among the riprap rocks and along the top of the banks. Willow

bundles (sections of a live willow roots with trunks and limbs attached) will be planted in appropriate-sized holes among the riprap rocks and along the tops of the banks.

4. IMMEDIATE MITIGATION OF CRITICAL THREATS:The two most critical areas being threatened with imminent loss are the Foreman shop and the TaborDam. As such, immediate action is required.

Mr. Glenn Foreman, owner of the subject Foreman property has characterizedthe need for immediatecritical mitigation on his property as,

"I think we wil-I see a repeat of last spring and summer with rapidloss of my riverbank. The river now is just 40 feet from my work shop(was 80 feet last winter) and I want to be able to dump rockimmediately in the sma1l gully east of the shop to prevent it fromundercutting the bank and taking out the road and backside of the shopbank. Saving the shop is my priority."

Similarly, the Tabors have recognizedthat losing the dam means losing the creek and access to their eastpasture, neither of which is acceptable. The encroachment is now less than 60 feet from taking the dam.

Both threats will be treated in similar ways by immediately placing large rock riprap into the twoaffected areas to sufficiently armor these remaining banks from continued erosion while the above threestabilization efforts can be completed.

Mr. Foreman has expressed his concern succinctly about this critical threat:"... this is an emergency and we need help and perhaps someemergency work to address the coming floods this spring. Thesnowpack is extreme in the upper snake river and f am afraid wewill see unprecedented damage by July.

I would like approval to dump large rocks in the small- gulleybetween the shop and the river this spring. AIso I foresee thedam eroding before the end of June and the escaping water willaccelerate flood damage to the littl-e bit of property leftbetween the river and my shop."

Also, to halt further erosion of the east bank of the Foreman and Tabor properties, construction shouldbegin as soon as possible to repair a portion of the peninsula to act as a jetty to stop the west path of theriver directly into Foreman's critical areas. Barb rock size gradation values will apply.

Please approve this application and request for help with the appropriate sense of urgency

Page 13 of 16 @ 2019 Glen Tabor All Rights Reserved

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INDEX

1. 1992-06 USGS Image (jpg)2. 2003-06 USGS Image (jpg)3. 2004-09 USGS Image (jpg)4. 2006-09 USGS Image (jpg)s. 2009-08 USGS Image (jpg)6. 20lI-09 USGS Image (jpg)7. 2013-08 USGS Image (jpe)8. 2014-10 USGS Image Upg)9. 2016-06 USGS Image (jpg)10.2017-06 USGS Image (jpg)

Page 14 of16 @ 2019 Glen Tabor All Rights Reserved

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APPENDIX 2= Barb Site lmages

INDEX

1. Barb Site Overviews Image (jpg)2. Barb A Views Image (jpg)3. Barb B Views Image (jpg)4. Barb C views Image (jpg)5. Barb D Views Image (jpg)

\*)Page 15 of16 @ 2019 Glen Tabor AII Rights Reserved

OVERVIEW: From East Looking Downstream

b A Looking East Upstream

A Looklng West Downatream

Barb B Looking East Upstream

Barb B Looking Across Rivera)

Barb B Looking Weet Downstream

Barb G Looking East Upstream

Barb G Looki s River

Barb G Looking West Downstream

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Barb D Looking East Upstream

APPENDIX 3: Gritical Parameter Values

INDEX

OHWM : Ordinary High-Water Mark = -10 feet below the natural top of the north bank

Dcr E Average Channel-forming Flow Depth: 10 ft at OIIWMw : Specific weight of water = 62.4lbs/cu.ft.

S. : Channel Gradient = 0.00123 or I.23 ft drop per 1,000 ft length

Sn = Slope of Constructed Bank = 2H:1Y = 26.6

CR = Radius of Curvature of North Bank of river between Barbs A & D = 560 ftWSW = Water Surface Width

At Minimum flow : 197 ft.

AtMaximum Flow = 238 feet

Wt = Total Channel-forming FlowWidth = 100 ftWerr E Total Channel-forming FlowWidth = 40 ft(CR/WSW)min flow, Stream Curvature Coefficient = 560 ft I 197 :2.842 C,nin 3 0.4(CR/WSW)max flow, Stream Curvature Coefficient = 560 ft I 238:2.35: Cmax = 0.4

K = Bank Slope Coefficient for bank slope of 2.00:1 = 0.72

O, Barb Angle = 30"

L, Barb Length =Ler / sin(O) = 25/0.50 = 50 ftLen, Effective Barb Length: y4 (100) = 25 ft.h."* , Barb Height = 6.0 ft.

Dsobarb , Barb Rock Size, = 2 x9.5 inches = 19 inches

Wn, Barb Width =76"Lr, Bank Key Length = 8 ft.

Dr, Bed Key Depth = 20 inches

Qnarn / Qtotar , Barb Flow Ratio = 0.375

Fr, Froude Number =2.34

H, Head over weir = 5.6 ftH+h=5.6+ 6=ll.6ftDzs

'ip."p , Bank Slope Rock Size = 19 inches

Page 16 of16 @ 2019 Glen Tabor All Rights Reserved