DES LACS RIVER FLOOD CONTROL STUDY BURKE, WARD, MOUNTRAIL, RENVILLE COUNTIES NORTH DAKOTA

CANADA

UNITED STATES

BURKE COUNTY

MOUNTBAIL COUNTY

RENVILLE COUNTY

WARD COUNTY

MINOT

PRELIMINARY ENGINEERING REPORT SWC PROJECT NO. 1772 NORTH DAKOTA STATE WATER COMMISSION APRIL, 1984

lti\,i PRELII4INARY ENGTNEERTNG REPORT

DES LACS FJ\ÆR BASIN STUDY

SWC PROJECT #L772

APRTL, t9g4

NORTH DÃKOT"A STATE VIATER COMII{ISSION 900 EAST BOIIITEVARD BTSMARCK, NORTH DAKOTA 58505

PREPARED BY:

WATER ENGIIÏEER

DALE L. Þfa HYDROLOGY AND ITWESTTGATIONS ENGINEER

D¿$ID A.. -8. DIRECTOR. OF ENGINEERING

VERNON FAHY, STATts SUMMARY

In May, 1983 the North Dakota State blater Commission entered into an agreement v¡ith the lrlard county Water Resource District to develop a hydrologic model and evaluate flooding problems in the Des Lacs River

Basin. A hydrologic computer model was used to estimate discharges on the tributaries and at selected points on the river.

Eight potential d.am sites were investigated for their potential to reduce flooding in the basin. It should, be pointed out that this report is not proposing that these dams be constructed at this Èime. If the lrlater Resource District. desires to pursue any particular dam or Èype of dam, a more detailed investigation would be reguired,.

The dams studied both individually and coll-ectively do not provide a large degree of flood. protection. The study shows that several dams would be required to reduce the flood peaks significantly. The follow- ing results pertain to the placement of dam sites.

1. Dams placed north of the Des Lacs Refuge would have litÈIe

downstream effect d.ue to the combined capacity of the refuge reservoirs.

2. Dams placed. in the middle portion of the basin provide the greatest fl-ood, red,uction. This is due to timing of flow from

the tribuÈaries being fairly cl-ose to the timing of the Des

Lacs River.

3. In the l-ower portion of the basin, the peak flows from Tasker,

Lloyd.s, and Larson Coulees were slightly ahead of the main stem peak. This would lessen the flood reduction benefit of

dam sites. In addition, it appears that dams eonstructed in the upper aseas of the triþutaries may be more sosÈ ef,fecÈive than tlre larger daqrs Located on the do¡¿rrsÈream end of the tributaries. For .exam¡lle' upstrean and, downstream dar¡rs were studied on f'laùen Coul,eer in Èhe Carpj.o area. A da¡q siite on the uPstream end of Ëhe cou]-ee re{uced the 100-year fLood peak at FOxlpIm by ?tr with a cosù of ,a¡rBroximately $305rO00. The doqnstrea:n d"anr reduced the peak by t2*, but the cost increased to $1'3 niltrion. t¡erall, the results of, the studli provide an esÈírnate of the costs and benefits that could be expected from dams of, various sizes and locations A review Ìras rnade of, the i:npact of drainage in the basin. Although, the gtudy showed that drainage could resul-t in an increase in peak fLows" it j-s unlikely thaÈ siqnif,icanÈ increasas have occuffed as a result of drainage. TABLE OF CONTENTS

Page

I INTRODUCT]ON.. I

II. DESCRIPTION OF THE BASIN 2 A. Location and Size 2 B. Topography and Geology. 2 C. Climate. 2 D. Flooding Probl-ems 4

III. EXISTING V,TATER PROJECTS 5 A Northgate Dam.. 5 B Des Lacs National füildlife Refuge Dams. 5 c Burlington Dam No. I 7 D Burlington Dam No. 2 7

IV. EXISTTNG STR.EA-M GAGE DATA 8

V STUDY APPROACH. 13 A. General 13 B. ¡4odel Development for Existing Conditions.... I3 C. Mode1 Development for Tributary Dam Analysis. 16

VI . STUDY RESULTS 19 A. Model Results for Existing Conditions l9 B. Model Results for Tributary Dams 2L C. Impacts of Drainage... 30 D. Souris River Flooding fmpacts 31

VTI. CONCLUSIONS... 33

TABLES

Table l- Des Lacs Ri-ver Basin Stream Gage Discharge Frequencies... 9 Table 2 Des Lacs River at Foxholm Stream Gage Data Summary. 11 Table 3 Des Lacs River at Foxholm Volume of Frequencies. L2 Table 4 Drainage Areas of Tributaries and. Des Lacs River. 15 Tab1e 5 l-979 Peak Discharge Times. 16 Table 6 Des Lacs River Frequencies... l9 Tabl-e 7 Statistics Summary of Potential Dam Sites. 23 Table 8 Peak Ðischarges on Des Lacs River at Foxholm with Individual Tributary Dams. 24 Table 9 Peak Discharges on Des Lacs River at Souris River Confluence with Individual Tributary Dams. 25 Table 10 Cost vs Flow Reduction, Tributary Dams SO-Year Flood. 27 Table l-l- Peak Flow Þy Frequencies with Multiple Dam Proj ects. 2A FIGURES

Figrure I General Location l,lap of t'he Des Lacs River Basin. 3 Figure 2 Existing lilater ProJects...... 6 Fig:ure 3 Hydrograph of 1969, L97O, and l-979 Recorded Floods on Èhe Des Lacs River at Foxholm IO Figure 4 Watershed LocationS L4 Figure 5 Hydrograph of 1979 Recorded Flood vs 5O-Year À4ode1ed Flows. 20 ')) Figure 6 Potentlal- Dam Site LocaÈions. !... .Figrre 7 Hydrograph of 5O-Year Flow: Existing vs Pl-an Three Dams, Des Lacs River at Foxholn.. - - 29

APPENDICES

.A.. InvestJ-g-ation Agreenent B. Area-CapaciÈy Curves for Potential Dam Sites C. Preliminary Cost Estimate for Potential- Dams

D. Individual- Dam Loeation MaPs I. INTRODUCTTON

The Des Lacs River has a history of flood problems. The lower Des

Lacs River has several steep coulees that enter the river from the west and cause extensive agricultural floodíng. In addition, minor urban flooding is experienced. There has been considerable speculation as to

Èhe measures that can be taken to decrease the flooding in the basin.

On May 6, l-983, the North Dakota State $Iater Commission entered into an agreement with the Vüard CounÈy V'later Resource Board. The pur- pose of this agreement was to develop a hydrologic computer model of the

Des Lacs River Basin. This modet would be capable of analyzing the general flooding problems in the basin as well as evaluating potential water projects. A copy of the agreement is included. in Appendix A.

The dams evaluated in this study were selected to provide a general analysis of different projects in terms of size, type, and. Iocation.

The basin has the potential for the construction of several other d.ams in addition to those included in this report.

-] - II. DESCRTPTTON OF THE BASIN

A. Location and Size

The Des Lacs River, a tribuÈary of the Souris River, has a total drainage area of Lr042 square miles. The head.waters of the river are in southern Saskatchewan. The Basin includes portions of Burke, Renville, Mountrail and lfard counties in North Dakota. Figure 1 is a general

Iocation map of the Des Lacs River Basin.

B. Geology and Topoqraphv

Ground moraine "pothole areas" and the broad river va11ey is char- acteristic of the Ðes Lacs River Basin. The soil consists mainly of well-d.rained loams and clay loams which are gently undulating. The southwest drainage d.ivide follows a band. of dead-ice moraines, wíth the basin having surficial glacial d.eposits which contain a broad pattern of meltwater channels.

Generallyr the upper reaches of the tribuÈary strearns have the major concentration of pothoJ-es. Many poÈhole areas are considered as non-contributing due to their lack of an outl-et. The downstream seg- ments of the tributaries have steep, well defined channels. This causes flooding to occur extremely fast from both rapid snowmelt and summer thunderstorms.

C. Climate

The Des Lacs River Basin climate is characterized by extreme varia- tions in temperature, variable rainfall and moderate snowfalt. Record.s of the National- Vùeather Service show thaÈ temperatures have varied from

-2- cAx^DA utattEo lf^lEl

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DES LACS RIVER BASIN XHOLM

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General Location Map Figure 1

-3- the lows in -5Oor to highs in llOor range. Annual- mean temperature is

39oF. Annua1 precipitation averages 15.5 inches. The mean precipita- tion ranges from a minimum of 0.4 in February to a maximum of 3.4 in June. The average annual snowfall is 33 inches.V

D. Fl-ood.ing Problems

Almost every year the Des La,cs River overflows its banks Èo some extent. Most floods are small and short in d.uration-! Severe floods have occurred in spring of L949, 1969, L97O, L975, L976, and 1979. I'lood.ing can also occur in the area of blocked. culverts or storm drains during periods of severe rainfall because of steep va1ley watts.V Only a few studies have been completed on flood problems in the basin. The Federal Huergency Management Agency has completed Flood. fnsurance Studies for the CiÈies of Burlington, Donnybrook, Carpio, and the unincorporated areas of Vtard County. The U.S. Army Corps of Engineers have studied the lower Des Lacs River from Foxholm to the mouth in conjunction with Burlington Dam invesÈigations.

IJ U.S. Army Corps of Engineers, Flood Control Lake Darling, Design Memorandum No. 3. 2/ North Dakota State üIater Commission, 1983 State trfater PIan. !/ Federal tnergency l4anagement Agency, Flood Insurance Study of Ward County.

-4- III. EXISTING VüATER PROJECTS

Several water projects have been construcÈed in Èhe Des Lacs River

Basin. Figure 2 shows the location of the larger projects. Below is a brief description of these projects:

A. Northgate Dam

Northgate Dam is located in Section 19, Township 163 North' Range

89 V'Iest, on SÈony Run Creek in norÈheastern Burke County. The City of

Northgate is located approxi:nately four miles north of the dam site. The dam was built. in 1968 exclusiveJ-y for recreation. The dam is 38 feet hiqh with a storage capacity of 11480 acre-feet at the conÈroI elevation.

B. Des Lacs National Witdlife Refuqe Dams

The refuge is Iocated in lriard and Burke Counties along the Des Lacs River. In 1935, the refuge was established for the restoration, devel- opmentf and preservaÈion of migratory waterfowl habitat. The dams are identified by number as 2, 3, 4A, 5, 6, 74, and 8' with #2 the farthest north and #8 the most downstream. General characteristics of the dams are a earthfill- embanlsnent, uncontrolled weir spillway, and stop log structures to regulate approximately the top 2 feet of each reservoir.

The average height of the dams above the flood plain is 4 feet' with the exception of #2, which is higher.V The mean water depths ïange from l-.1 to 8.1 feet. The reservoirs have a combined, capacity of 4'7,OOO acre-feet and, as a result, have a strong influence on the Des I-a'cs River from the upper watershed.s.Z

t/ North Dakota State I¡'Iater Commission, Dam Safety Report, North- gate Dan. 2/ U.S. Army Corps of Engineers, Burlington Dam.

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DES LACS RIVER BASIìl ìF

I I Northgate Dam 2 Des Lacs NVIR Dam #2 t 3 Des Lacs NVIR Dam #3 4 Des Lacs NVüR Dam #4a 5 Des Lacs NbIR Dan 'j- #5 !- t 6 Des Lacs NbfR Dam #6 i*j -' 7 Des Lacs NWR Dam #74 8 Des Lacs NWR Dam #8 9 Burlington Dam #2 l_0 Burlington Dam #f

Existing Water projects Figure 2

-6- C. Burlington Dam No. 1

Burlington Dam No. I is located on the Des Lacs River about two miles northwest of Burlington, along the north side of U.S. Highway 2 and 52. The dam built in 1936 was initial-ly constructed for irrigating lands in the Burlington ProjecÈ area. The dam is 2I feet high and has maximum pool storage of 567 acre-feet.V

D. Burlinqton Dam No. 2

Burlington Dam No. 2 is located on the Des Lacs River about 3.5 miles northwest of Burlington, along the north sid,e of U.S. Highway 2 and 52. The dam built in 1938 \^ras constructed to provide add.itional

\^rater for irrigation. This was to supplement Burlington Dam No. l's water supply d.uring a drought year. Tbday, irrigation is minimal with it being used for its recreational value. The dam is 24 feet above the streambed and has a maxímum pool storage of 487 acre-feet-U

L/ U.S. Army Corps of Engineers, Burlington Dam No. I 4 U.S. Army Corps of Engineers, Burlington Dam No. 2

-7- TV. EXISTTNG STREAM GAGING DATA ExisÈing strean gaging daÈa in the Des Lacs River Basin is cur- rently collected at only one station - the Des l-acs River at Foxholm- This continuous gage has approxirnately 40 years of record (1905-06' 1946-present). Two crest stage stations were operated on tributaries from 1957 -L973. The crest stage stations only provided peak flows for each year of record. The U.S. Fish and Vüildlife Service records lake elevations on the refuge pools. These records are prJ:narily collected during 1ow flow periods. The staff gages are nonnally overtopped during flood. periods. Table 1 presenÈs Log-Pearson Type III flow frequencies for the Des Lacs River at Foxholm and the two tributary gages. The highest recorded flood peak on the Des Lacs River at Foxholm was 4260 cubLc feet per

second on Aprit 19, 1979. The 1979 flood was caused by a rapid snow- melt. Figure 3 is a hydrograph pJ-ot of the three high floods on the Des

Lacs River at Foxholm, 1969 | I97O, and L979. The day of peak was centered on the same day for each year. The three hydrographs all show a rather high initial peak discharge and a Iower extend.ed. flow resulting from releases from the u.s. Fish and wildlife service Refuges. Table 2 lists the annual peak discharge, the 30-day high volume and the annual volume of flow on the Des la.cs River at Foxholm. The highest

volume year \^ias 1976 with over 107r000 acre-feet flowing past Foxholm. A freguency analysis of the 30-day high vol1¡ne flood for the Des Lacs

River at Foxholm is shown in Table 3.

-8- TABTE 1 - DES LA,CS RT\TER BASTN STREAM GÃGE PEAK DTSCHARGE FREQUENCIES

Frequency

Strean Gage 1O-Year 25-Year SO-Year 100-Year -GrÐ ("fÐ '(.fÐ (cfs)

Des lJacs River at Foxhol-m (5I Years - Drainage area: 944 sq- mi.) 2r 000 3r100 4,1OO 5,2OO

Des lJacs River TributAry near Donnybrook (Drainage Ar.ea: 3.8 sq. mi. Record: 18 years) ].75 250 300 * Fuller Coulee at Foxholm (Drainage Area: 12.8 sq. mi. Record: 19 Years) 250 400 500 *

*Insufficient r'ecord length to estimate.

-9- DES LRCS R I VER RT FOXHOLII REC0RDED |-IYOR0GRRPHS t 969 1,970 1.979 q ¡

rnE rr 1970 c¡ x a - 1979 I \ {.Eì

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I b3 oH 2.8 I ts3fl I \\ Ëe EçI I \\ (J 14 øñ I ¡ t-l / ¡ r^ì I ct / I I t\ q I \ E t l \ \ L J \- I \ I , ì \ -l l-'¡ c¡ I a P'l H H I ct ) -J 0.0 2.o l.D 6.0 8.0 10.0 l2.o l{.0 16.0 18.0 ?Í).o 72.0 2l.o 26,0 28.0 311.0 IIIIE TN DRYS Figure 3 TABLE 2 - DES LACS RT\ÆR AT FOXHOLM STREAIVT GAGE DATA SUMMARY

Year Peak Discharge 30-Dav Hiqh Volume I Year Vo1ume (cf s) (acre-feet) (acre-feet)

I905 100 1,200 3,300 1906 350 3, 600 6,7OO I939 I,22O L946 l_13 2, OOO 2,5OO l-947 640 8,700 11,600 L948 505 13, 600 20, 300 l-949 2 tOOO 2r,500 29,OOO 1950 1, 010 17r 3oo 34, o0o r95I 1,9 00 26,4OO 45,600 L952 850 11,800 l-6,7OO 1953 775 8r800 15, 900 l-954 205 3, 300 12, 300 1955 900 Il_, 500 29,7OO r956 696 r0,100 31,100 L957 r50 1,700 3, 900 1958 430 4 tTOO 5, 140 1959 105 1, 0o0 1,700 I960 I,O2O 18, 200 2I,7OO 1961 25 400 600 L962 50 500 900 1963 934 6, r00 8, 7oo 1964 355 3, 400 5,900 1965 406 5,4OO 12, 300 L966 250 3,300 g r4oo l-967 530 4, 300 5,700 L968 85 900 2, OOO 7969 2,460 30,800 52, 800 ]-970 3 ,660 33, 300 63,000 T97T 193 3, 200 8, 000 r972 1,030 19r 800 60, 900 r973 529 3, 700 14, 500 L974 650 17, 100 47,gOO r975 2,6'70 44 | 600 89,000 L916 l, 550 49r 800 107, l_00 L977 42 700 2,LOO L978 700 1,500 10,l_00 L979 4,260 38r 000 60, 800 1980 230 2,4OO 9,4OO 1981 580 4,600 6,4OO L9A2 100 11,800 19, 500 1983 350 10,500 23,9OO

-11- TABLE 3 - DES LACS RIVER AT FOKIOLM Volume of Freguencies

FrequencY 30-Day Volume (acre-feet)

5 year r8, 300

10 year 29,600

25 year 48, 000

50 year 64,4OO

100 year 83, 000

-L2- V. STUDY APPROACH

A- General

A numerical model using the Corps of Engineers Computer Program

HEC-I, Flood Hydrograph Package was used to d,evelop flow hydrographs in the Des Lacs River Basin. A hydrograph is a representation of the distribution of flow with respect to time. The HEc-1 model has several options available for hyd.rograph development, loss rate computation and, routing procedures. this study utilized the Synder Unit hydrograph, the

SCS Curve Nu¡nber Loss Rate and, the Muskingum routing method.s.

B. Mod.el Development for Existing Conditions

the Des Lacs River Basin was divided into over 30 separate sub- basins. Figure 4 shows the subbasins included j-n the model. Table 4 lists the subbasins and the drainage area of each subbasin and the Des

Lacs River at selected, locations. Hydrographs were d.eveloped for each of the subbasins and at several poinÈs along the Des Lacs River.

The Muskingun routing method. was used to sj¡nulate flood-fIo\^r move- ments from one river reach to the next. Reach travel times were esti- mated based on information provided by the National Vüeather Service on flow movements. Table 5 shows the time of the peak discharge at loca- tions along the Des Lacs and Souris River. This information, during the

1979 spring flood also correlates to information available on the 1969 Des Lacs River flood.

-13- U trf z* a) o rt E c) ft CA !ú pr{Ø H @ QPJOortO o ì/ -¡/ PJFiE H slif l-J(/)È tÉ o 5tt o prots (nÞ \ : :o Èo H a ÞÈ z ¿ OJ t. är¡ ) ôo > ofi @ li PJ D) Èl- ts- @ ø tr¡ Fì rt i € PJP.o ( pr ÞHì rf I o @ rd fJ ts. ul w4f.' "o'tr, ,ô. (aif "ouvt r a, FlÉo p, -("ó"" o . Fa \ ,Þ5 l¡-r \ o I p, ts ct È H. I o Þ "."r*."úl:r, at ltqø ¡.ru,...1T*,'^ I -eùN t y i - ' ¡'sl .- '!¡s'- " r'! ' s/ a lu-.^^tu¿,-,r'û- '- ìio fíj¡f''íirnoc oil p' À'/¡-"/å ,f (5¡¡'':-l q-tt I \

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c TABLE4-DRATNAGEAREAS OF TRIBUTARIES AND DES LACS RIVER

Drainage Area Drainage Area Des Lacs River No Watershed sq. Mi. Sq. Mi.

I Northgate & Canada 57.7 57 .8 2 Northgate Dam I23.8 181.6 3 Stony Run 54.3 235.9 4 Unnamed V'iatershed 2L, 22-162-88 50. 5 286.4 5 Nine Mile Corner 60.3 346.7 6 Thompson Lake 42.6 7 Shockley Slougrh 57.L I Stony Creek 55.4 501.8 Dan #2 50r.8 o Ankenbauer Coulee 23.3 525.L 10. Niobe Coulee 43.9 569. 0 Dam #3 Kenmare 569. 0 11. Taskers Coulee 42.3 611. 3 Dam #44 611.3 L2. Dam #6 76.4 627 .7 Dam #74 I3 Baden Coulee 21-.7 649.4 Dam #8 649.4 14. Mott Coulee 14.L 663 .5 15. Spencer Coulee 42. O 705.5 16. Berg Coulee 9.8 715.3 17. Bowman-Shipton Coulee L2.O 727.3 Donneybrook 727 .3 18. Aurelia 38.0 765.3 19. Carl- Feldner 48.2 813.5 20. Flaten Coulee 20.3 833 .8 Carpio 833.8 2L. Joh¡son Coulee 18. 7 852.5 22. Oleaas Coul-ee 18. 4 870.9 23. Hanson Coul-ee o 6 880.5 24. Arnold Coulee )) 6 903.1 25. Blacks Coulee 18. U 92L.L 26. Karl-sen-Fuller Coulee )) 7 943.8 Foxholm 943 .8 27. Lonetree Trib. Dam 6.9 28. Lonetree Trib. 7.7 ¿9- Lower Lonetree Coulee l-O.7 969.L 30. Tasker Coulee 23.O 992.I 3l-. Lloyds e Kandolph Coulees 30.0 l-o22.L 32- Larsons Coulee 20.4 LO42.5 Confluence with Souris River LO42.5

-15- TABLE 5 - 1979 PEAK DISCHARGE TIMES

Location Time of Peak

Des Lacs River at Donnybrook April 18, l-979 - 8:00 P.M. (+2 hrs. )

Des Lacs River at Carpio April 19, 1979 - 1:00 A.M. (t2 hrs. ) Des Lacs River at Foxholm April 19, L979 - 8:00 A.M.

Ðes Lacs River Peak aÈ Minot April 20, L979 (Early A.M.)

The Des Lacs River at Foxholm stream gage was the primary station used to calibrate the computer model. A log-Pearson Type III statistical analysis of the stream gage d.ata provid.ed flows for the 10, 25, 50 and

100-year flood peak discharges (See Table 1). The model results were compared. wiÈh the gage data and small adjustments to model inputs were made to reproduce log-Pearson peak d.ischarges.

Once the hydrologic model was calibrated, there were 55 reference points in the Des Lacs River Basin at which specific information hras available. The available information at each point inctudes contrib- uting drainage area, peak discharge, volume of runoff and the discharge flood hydrograph.

C. I"lodel- Development For Tributary Dam Analysis After the model was d.eveloped for existing conditions, several potential dam projects were added to the model. This provid.ed flow hydrographs with and without the dams at locations below each dam site. The dam sites were selected Èo provide an areal distribution of the projects as weII as a variety of sizes. This provided for a comparison of costs and. flood benefits for different tlpes of dams. It was not the

-16- intent to include enough dams to control- a particular size flood. The different tlpes of dams studied provided an indication of the more feasible dam locations, and Èhe flood reductions that could, be antic- ipated with various projects.

A1l- dams were consid.ered as dry dams for flood contror purposes. The dams would conÈai-n r^rater only d.uring flood period,s. The dams includêd in this analysis were located on tributaries to the Des Lacs River and not on the main stem. I,lain stem dams would. require detailed design and were considered beyond. the scope of this study. The general criteria for locating the dams were:

l-) No farmsteads could be inundated. by the reservoir pool area.

2) No county or farm to market road could be closed..

3) A dam 30 feet or higher must have the capability to contain a 1OO-year snowmelt flood without passing water through the emergency spillway. Dams less than 30 feet high must contain the 5O-year flood.

For dam safety purposes, dams located above a ciÈy or farmsteads were designed. more conservatively. These dams were designed with flatter side slopes and rock riprap \^Ias incl-uded for the entj-re upstream face of the dam. These dams would also be required to pass a probable maximum precipitation frood without overtopping. A grassed emergency spirrway was used to pass the rarge floods. Detailed design studies would be required. before a high hazard d.am could be constructed.

For dams l-ess than 30 feet high, minimal riprap was included in the cost estimate. rn addition, corrugated metal pipes and, sid.e sJ-opes of

3:1 upstream and 2:l- downstream were used.

Land costs r^/ere considered separately. The land for the d.am, emergency spil1way, and. sed.iment pool areas were assumed. to be purchased.

-I7 - at a cost of $500 per acre. Fl-ood easements r¡¡ere assumed to be suitable for an area of I.5 times the flooded area at the emergency spillway pooJ- elevation. Flood easements were estimated at $300 per acre.

-r8- VI. STUDY RESULTS

A. Model Results For Existinq Conditions

The initial step in the model development was to calibrate the HEC-

I model. The 1979 flood was the mosÈ recent and largest record.ed flood and, therefore was used as the base flood for calibration. A statistical analysis of records on the Des Lacs River at Foxholm determined that the

1979 flood was a SO-year event. Figure 5 compares the 1979 recorded flood with the 5O-year modeled flood. The second, step in the exísting conditions mod.el was to modify the precipiiatíon volunes to correspond. with the 10, 25,50 and.100-year peak flows for the Des Lacs River at

FoxhoIm.

After the model was cal-ibrated to the Foxholm strean gage, peak discharges h¡ere determined for other points along the Des Tacs River.

Table 6 shows d.ifferent frequency discharges for the Des Lacs River at the United States,/Canadian border, at Donnybrook, Carpio, Foxholm and at the confluence with the Souris River.

TABLE 6 - DES I.ACS RIVER FREQUENCIES

Des Lacs River Peak Discharge Freguency Location IO-Year 25-Year 5O-Year 100-Year (cf s) (cf s) (cf s) (cf s)

Near Canad.ian Border 200 300 400 500

Donnybrook 680 l, ogo 1,490 l_,850

Carpio Lt32O 2, O5O 2,760 3 t42O

Foxholm 2, 000 3, I00 4,2OO 5,2OO

Souris River Confluence 2,5OO 3, 900 5,25O 6,500

-19- DES LRCS RIVER RT FOXHOLM 1929 RECORDEO VS 50 YERR I,|ODELEO FL[]I,{S ct a B ¡,ì¡o ! - 1979 C¡ tr-50 YR a \ C'I rË \ cn

I b: \ oN) 2.8 I t-. ¡1, (9ftt Ee I (r)ñãE l-l o \ c¡ I f, c¡I \ \ 4 H - I aa c, J 0.0 2-O {.0 6.0 8.0 10,0 Lz.Íl ll.0 16.0 19.0 æ.o 22.o TIHE IN DRT5 Figure 5 The refuge pools, although not constructed or operated for flood control, do provide flood benefits to the lower Des Lacs River. The upstream coulees in the Des Lacs River are not as sÈeep as the lower basin coulees and, therefore, a double peak (the 2nd being smaller than the first) would naturally occur. The coml¡ined. refuge pools have a

Iarge storagie capacity and, this results in a greater separation of the peaks and a significant decrease in the magnitude of the second peak.

B. Modet Results For Tributary Darns

Eight dams were included in the final analysis. The locations of these dams are shoh¡n on Figure 6. Several other dams were studied but were not included due to a variety of reasons. Since Èhe lower Des Lacs River peak results from the coulees below the Fish and Wildlife Refuges, dams north of the refuges had little d,ownstream benefit. In add'ition' the tributaries in the lower Des Lacs River basin (namely Tasker, Lloyds and Larson Coulees) were slightly ahead of the main-stem peak. There- fore, less reduction in flood flows from these areas was noted than from tributaries in the rniddl-e watershed areas. The eight dams shown in this study are all located on coulees and tributaries between Donnybrook and the lonetree-Berthold area.

Surunary sEatisÈics on each site are shown in Table 7. Area-capacity curves, individual site Iocation maps and. cost estimates for each dam are shown in Append.ices A, B, and C' resPectively-

The impact on peak discharges on the Des Lacs River at Foxholm and at the Souris River confluence is shown in Tables 8 and 9, respectively.

These tables show that Lolì/er Flaten Dam has the largest flood-flow reduction. However, Èhe cost of this project is also very high-

-2I- PIOPiOÜD DAI 3ITE¡ 1. Aurelie 2. Feldner 5. Hartland 4. tlppcr Flaten 5. Louer Flaten Þ 6. Arnold 2 7. Lonet¡ee Trib. z ()e Lover Lonetree of 8. C) l¡l J ¿ ¡lI G

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a Dt8 L^Ct

Potential Dam Site Locations Figure 6 -22- TABLE 7 - STATfSTTCS SUMMARY OF POTENTIAL DAM STTES

Emergency Storage at Acreage at Location Drainage Dam Top of spi1lv/ay Pipe Emergency Emergency S-T-R Area Height Dam Elev. Elev. Size & Type Spillway Spillway ( (acres) Name V'Iard Co. . rni. ) feet feet feet (inches acre-feet Cost

Aurelia NVt23 -158-87 3.5 34 I,832.O It821.O 24" RCP 190 13 -2 Dam ç L24,4OO Land 6,700 $ 131,100

Feldner svü 4-157-86 4-7 42 L,922.O L,9I7.O 24" RCP 280 19.8 Dam $ 129,5OO Land 9,500 $ r39,0oo

Hartland NEr6-157-86 6.9 44 Lt962.O I,951.O 24" RCP 580 57 Dam ç 284,765 Land 26,9OO $ 3Ir,665

Upper Flaten sEl-5-157-86 l-3.5 55 1,g35.o L,929.O 24" RCP 930 58.2 Dam $ 291, 000 I Land 27 NJ t2OO t 318,200 I $

Lower Flaten SI/t]2-157-86 20.3 83 l-,816.o 1,810.o 24" RCP L,77 5 61.0 Dam çL,327,898 I*:nd 28,7OO $l, 356,598

Arnold NVr 1-156-86 18.r 65 1,915.0 1,91-0.0 30" RCP 1,3r0 7r.5 Dam $ 27O,2OO Land 34, 000 $ 304, 200

Lonetree Trib. sw34-156-86 6.9 15 2tO76.O 2,072.0 30" CMP 460 1r1.6 Dam $ 32,IOO Land 50r 5oo $ 82,600

Lower Lonetree SVüI2-I56-84 25.3 70 r,722.O L,7r6.o 30" RCP 2, O5O 85 Dam $ 796,800 Land 92, 500 $ 889,3oo TABLE 8 - PEAK DISC'HARGES ON DES LACS RTVER AT FOXIIOI.,M !üTTH INDTVIDUAT TRIBUTARY ÐA¡4S

Exlsting Condltions Aurella FeLdner Hêrtland Upper Flaten I¡r¡¡er Flaten Arno]-d Lonetree trrib. Lo$ter Lonetree DaJn Dam Dam

10 Year 1,980 Lr960 L,965 l,940 1,875 1r800 1,gLo 1r 980 1,980

25 Year 3'100 3r060 3r060 3, 020 2,9OO 2 t79O 2,t945 NA NA

50 Year 4,180 4r130 4r13O 4,07Q 3r 910 3r750 3r960 4, L8o 4r18O 5,2oo 5, 200 100 Year 5 r2AO 5r130 5r105 5r 035 4,850 4t64A 4r890

I Èf\J I TABLE 9 - PEAK DISCHARGES ON DES I,ACS RTVER AT SOURTS RI\¡ER CONFLUEI{CE WITH INDIVIDUAL TRIBUTARÏ DAMS

Existing Conditions Aurelia Feldner Iiartland UPPer F1aten I-ohrer FlateR Arnold Lonetree 'Trlb. Lower Lonetree no Dam Dam

l0 Year 2,5O5 2'r49O 2,49A 2,465 2,4L0 2i34O 2,4L5 2,480 2t4O5

25 Year 3r880 3 r855 3,840 3r805 3,725 3, 6l-0 3,705 3,83O 3r695

50 Year 5 1235 5,l_95 5,175 5, i25 5, O2O 4,87O 41964 5,165 4 r 950

1OO Year 6r48O 6,43O 6r395 6,335 6t2r5 6, 03o 6tL25 6,385 6,100

I N) ur I In order to relate the cost of each project with flow reductíon, a comparison was d.eveloped between Èhe cost of each project and the flow reduction achieved by each individual project (Table l0). Based on this comparison, Uppeï Fl-aten and Arno1d Dams n-lr" an" lowest cost per unit of flow reduction on the Des Lacs River. This technique does not replace the need of a more d.etailed benefiÈ-cost analysis. If it. is d.esired. to pursue any one of the projects, a d.etailed analysis should be made to determine the benefits on the Des Lacs and. Souris Rivers. Three plans were analyzed to determine the cumulative effect of multiple projects. Pl-an 1 consisted of Arnold and. Upper F1aÈen Dams.

Plan 2 added the LoneÈree Tributary dam to Plan I, and. Plan 3 added

Feldner Dam to Plan 2. The cumulative impact of these plans are in

Tabl-e fl-. Figure 7 is a comparison of the SO-year hyd.rograph for the

Des Lacs River at Foxholm with and without the Plan 3 dams.

The results show a rather low reduction in overall flooding on the

Des Lacs River due to one to four d,ams. The reason is due to the large number of small coulees that influence the flooding on the Des Lacs

River. At the Souris River confluence, the Des lacs River has a con- tributing drainage area of 900 square miles. Plan 3 with four dams, only controls 43.2 square miles, or 4.8t of the total watershed. The decrease in peak discharge for Plan 3 ranges from 9t for the lO-year to l-3% for the 100-year flood. Irlhile this indicates that certain coulees have a greater influence on flooding Èhan others, the results also show that several dams would be required to decrease floodinq by 25-50t.

-26- TABTE 10 - COST VS FÜCTÍ REDUCTION TRTBUTARY DA}4S SO-YEAR FLCOD

Proiect Nane Pf,oject Cost $ Foxholm Souris River Mouth

Aurelia Dam $ 13L,O00 2.6 3.3

Feldner Dam 139,000 2.6 2.3

Hartland Dart 312, O0O 2.8 2.9

Upper Flaten Dam 3 L8, 000 r.2 1.5

Lower Flat,en Dam 1 r 356, 600 3. t_ 3.7

Arno]-d DaÍl 304, O00 r.4 1.1 Lonetree tributary Dan 83 r 000 L.2

Lo\À¡er Lonetree Da¡! 889, O0O 3.1

-¿t- TABT,E 11 - PEAK FLO!ú Ev FREQUENCTES Vt TIl }4ULTIPLE DAM PROJECTS

DES LACS RIVER AT FOXHOL}{ DES LACS AT SOUBIS RIVER CONFLUENEE fs Number 0 eaï 2

ExistÍng I¡982 3, 094 4,!82 5r 193 2,5A4 3r879 5 t234 6,478

Plan 1 (Arnold & Flaten Dam) 1r808 2,755 3r 688 4 1544 2t324 3r541 4,,736 5,936

Plan 2 (Pl-an I plus Lonetree Trib. oan) 1,808 2 ¡75,5 31 698 4r544 2r3O2 3, 501 4,666 5,74r

Plan 3 (Ptan 2 plus 2 3 4,607 5,659 I Feldner Dam) 1r 8O3 2,73O 3, 633 4,567 t287 1467 t\) @ I DES LRCS R I VER RT FOXHOLII 50 YERR FLO,.I ! EX I SI I NG VS PLRN 3 DRHS ? Ë rf1 A - EXISTING E¡ q / - J4ITH DRMS I \ GI3

CT' i b3 \ I N) \o =8¡-¡ lll I t¡l c.Ð f Ee, ¿ I t-lHR c¡ \ I/ c, a \ ¡.*- Ict \ J L r -t L

a C¡ aa J 0.0 2.o {.0 6.0 8.0 10.0 Lz.O Ir.0 16.0 18.0 æ.o z2.g TII1E TN DRTS Figure 7 C. I¡qpacts of Drainaqe

The Des Lacs River is characterized by a main peak flow from the steep coulee areas and a rather long sustained recession flow from the upper watershed areas. The lower portions of these coulees have very few natural wetlands or potholes and, therefore, drainage is not a factor. However, the upper portions of these coulees are relaÈive]y flat cropland areas with a large concentration of potholes. Agricul- tural drainage has been active in these areas. In recent. years Èhere has been increased concern regarding downstream flooding impacts as a result of the agricultural drainage- Drainage can influence peak dis- charges and flood, volumes by changing vetocity, decreasing the channel lengths, increasing the contributing drainage area' and by reducing the upstrecrm storage. To test the impacts of drainage, several changes \^/ere made to the i-nput parameters of the calibrated hydrology nodel. One or more of the fotlowing changes were made:

l) Reduce the time of concentrations; (Due to higher stream flow velocities) 2) Increase the drainage areas;

3) Decreased the nrrrnber of depressions.

The results showed increase in the peak flows and volumes from the individual watersheds. However, the impact on flows in the Des Lacs River was dependent on the timing of the tributary and main stem peaks. For example, a l-0 to 158 increase in peak discharges on a tributary resulted in only a L-2t increase in the Des River peak discharges.

Collectively, a 7 to 15å increase on all the tributaries resulted in a

7% increase at Foxholm and 4-6* increase at the Des Lacs River con- fluence with the Souris River.

-3 0- Therefore, it appears that a substantial amount of drainage would have to occur in the upper tributaries to significantly increase Èhe peak discharges on the Des Lacs River. The volume of flow can be in- creased more significantly than the peak discharge.

D. Souris River Floodinq Tmpacts

A brief review was made on the impact of Des Lacs River tributary dams on Souris River flows at Minot. The Souris River aÈ Minot usually has two peaks that occur one to three weeks apart. The first peak results from the Des Lacs River and, Souris River coulees upstream from

Minot. The second and. largest peak results from rel-eases from Lake

Darling Dam. The tributary dams in the Des Lacs River basin would. decrease Souris River flood.ing during the first peak. Although un1ike1y, the dams could. decrease flooding durinq the second peak if the peaks were only a fe\nr days apart. It is more likely that the Des Lacs River tributary dams woul-d slightly increase Souris River flooding during the

second peak. Without the dams, the Des Lacs River \^rater woul-d, be past l4inot before the second peak. Vüith the dams, however, d.ischarges may stilL be occurring as the second peak reached Minot. There have been two primary proposals for controlling Souris River

flooding. The Burlington Dam project would. includ.e a large dam on the Souris Ri-ver and a Des Lacs River diversion tunnel and control struc-

ture. Therefore, both Souris and. Des Lacs River flows would be con-

trol-l-ed- The tributary dams studied in this report would be above the Des Lacs River diversion bypass and would not affect the Souris River

fl-ows. The Burlington Dam project has considerable opposition and it is not likely to be constructed in the near future.

-31- Efforts are eur:rently beíng directed at an enlargement of, thè fl_ood storage capacitlt in l,ake Darling Dalr. This project wotrl-d control about a 35-yanr f'leod on the Souris nÍ¡¡e¡ but rrould not controL the Des lå,cs Rirrer. TriJcutarl' dans j.n the Ees Lacs Fllver Basin ¡'¡ould provide lj-rnited benefits to the Ssuris RLver with the :raising of Lake Þarling Ðiim. The timing of the De,s r.acs and souris, R:ive-r fLows rooul-d be ¿n importan¡ sonsideration.

-32- VII. CONCLUSTONS

The model d,eveloped for the Des Lacs River basin does represent the existing conditions and can be used as an effective tool to analyze flooding in the basin. Based on results of this model, the following general conclusions can be d.rawn.

1. The peak discharges along the lower Des Lacs River are the result of flows from the steep coulee areas located primarily

between the towns of Donnybrook and Des Lacs. Dam projects constructed in these areas would be the most effective in controlling flooding.

2. The Des Lacs River above the Fish and ü7i1d1ife Refuges normally peaks l-ater and at a lower discharge than the lower coulee flows.

3. Several tributary d.ams would be necessary to control flooding on the Des r,acs River.

4. Dams constructed in the upper areas of the tribuÈaries may be

more cost effective than dams constructed, in Èhe downstream

areas. As one example, upstream and downstream dams were studied, on Flaten Coulee in the Carpio area. The dam site l-ocated approximately four miles upstream of the confluence

reduced the 100-year flood peak on the Des Lacs River at

Foxholm by 72, with an estimated cost of $305,000. The d.own- stream dam, located near Èhe confluence of Flaten Coulee,

reduced the Foxholm peak by I2z but the cost increased to $1.3 million.

5. It is unlikely that drainage has significantly increased. peak

d.ischarges in the lower Des Lacs River.

-33- APPENDÏX A

InvesÈigation Agreement May 6' 1983 StüC ProjecL #L772 AGREEMENT

Investigation of the Des Lacs River Watershed,

T. PARTIES

THIS AGREEMENT is between the NorÈh Dakota State lrlater Commission' hereinafÈer referred to as the Conrnission, acting through the State Engineer, Vernon Fahy; and the Ward County Water Resource Board, here- inafter referred to as the Board,, acting through its Chairman, Arden

Haner.

II. PROJECT, LOCATTON A}üD PURPOSE

The Board wishes to evaluate the flooding potential along the Des

Lac Rj-ver and develop a hydrologic model of the watershed. The model wiII be a \^rater management tool that can be used to evaluate the effects of future projects in the Des Lacs River Basin. Approximately three potential dam sites will be located and evaluated according to their flow reduction capacity. A very preliminary design wilt be d.one for these sites based on a field measured profile and information from topographic maps. This design will not result in a set of plans for construction but rather is intend.ed to provide general cost and hydrology information.

The project area will consist of the watershed of the Des Lacs River above its conftuence with the Souris River- Fie1d surveys will be done to gather information necessary for the development of the hydrologic nodel. FIow rates will be determined' at the mouth of the Des Lacs RiVer and at other selected' points on the main stem.

-t- 1IT. PRELTMTNARY INVESTIGATTON

The Parties agree Èhat further information is necessary in order to evaluate the flooding problems in the project area and' develop a hydrol- ogic model. Therefore, the Commission shall conduct an investígation consisting of the following: 1. Do necessary field work to set up the model. This will con- sist of cross-sections at hydrologically important locations

and the measurement of structures that will affect the hydrol- ogy of the Project area. 2. Sel_ect approximately three potential dam sites that would ternporarily retain flood \^¡aters. A profile along the poten- tial aligilnent of the sites will be taken in the field.

3. Do a preliminary design of the proposed. dams based on the

measured profile and information from topographic maps.

4. Devel_op and calibrate a hydrologic model of the project area. 5. Determine the flow rates for the f0' 25, 50 and l-OO-year events at the mouth of the Des Lacs River and at selected points of importance along the main stem. These flow rates will- reflect present conditions"

6. Develop preliminary cost estimates of any proposed retention

d.ams based on the preliminary design- 7. prepare a Preli-minary Engineering Report that would describe the present hydrologic conditions, evaluate potential projects, present preliminary project designs and their estimated costs.

If the Board decided to proceed furÈher wiÈh any potential project identified in this preliminary investigation, more detailed information and a more detailed study would. be needed to develop plans for construction

-2- This is beyond the scope of this investigation and would have to do done under a seParate agreement.

ÏV. DEPOSTT - REFUND The Board shall deposit a total of $2,200 with the Commission to partially defray the costs of Èhe investigation. Upon receipt of a request from the Board to terminate proceeding further with the pre- liminary investigation or upon a breach of this agreement by any of the parties, the Commission shall provid.e the Board with a statement of all expenses incurred. in the investigatj-on and shalt refund to the Board any unexpended. funds.

V. RTGHTS OF ENTRY

The Board agrees to obtain written permission from any affected, landowners for field investigations by the Conunission which are required for the preliminary investigation. The Commission shall inform the

Board of the locations where surveys are needed.

VI. TNDEMNTFICATION

The Board hereby accepts responsibility for and holds Èhe Commission harmless from aI1 claims for d.amages to publj-c or private property, rights or persons arising out of the project and the travel to and. from the project area by the Board or any of it.s subcontracÈors, agents, or employees. In the event such a suit is initiated or judgement entered against the Commission, the Board will indemnify the Commission for any settlement arrived at or judgenrent satisfied.. No indernnification will be required. of the Board for claims resulting from negligent acts of the

Commission.

-3- VII. CIIAÑGES TO TIIE AGREEMEì{IT

Changes to any eontractual provisions herein will not be effective or bindingr unless such changes are made ín writinq' signed by both parties. and attached hereÈo.

óL.).{1.e

Chairoan State Engineer /r t- t3-y3

I I

-4- APPENDTX B

Area-Capacity C'ürves For Potential Dam Sites RURELIR DfiM S23_T158-RBZ RRER CRPRCITY ct a EI @ ¿/

c¡ I _/ ct -/ æ{.

J ú'l o 2.8=.,' Fa -¡

I td F â / I Ëq

JäE CL¡ /

aa ct / @ + - RRER ¿ CflFÊCITY ct - a t ct / ct @ t / 0.0 +.o 8.0 Lz.O 16.0 ?ß.o 2+.O 2E.O RRER TN NCfrES

0.0 lm.0 200.0 500.0 ,fÍ10.0 500.0 600.0 7ü).0 CRPRCTTY TN RCRE-FEET FELDNER DRM S4-T 1 5Z-R86 RRER CRPRCTTY aa otfl a c¡I otÍ. ,/ (Ð a / r9B E '- Ct =B' I tú (Js N) l-l= . I Fls| f¡.: ol >d t¡.l f I d3 / gtct /'

aa (ttc¡ I + - RRER @ ¡lr I C' @ @ / 0.0 5.0 10.0 15.0 æ.o 25.0 Il.0 35.0 ill.0 RREN TN RCRE5

0,0 200.0 l{to.0 6(n.0 600.0 1000.0 lãn.o 1t00.0 16110.0 CRPRETTY TN RCRE-FEEI UPPER FLRTEN COULEE DflM S15 -TT57 -R86 ÊRER CRPRCTTY q B o) -1 a I 7 tl.c¡ o¡

c¡ gI gr9 lLO

I =d tú z. UJ Cls I t-l ¡ t-.c6 Cl Þ¡ t!¡ uo-Ja c, / ot I c, cta / + RRER o) - ó I G' a ^ C' @ I @ 0.0 10.0 20.o x0.0 ß.o gr.0 æ.0 7Cl.O tl.o 9l¡.0 [fn.o RRER TN NCRES

0.0 250.0 g¡0.0 750.0 1000.0 1ã0.0 lgl0.0 1750.0 ?m.o z?5o.o 25m.0 CRPRCTTY TN RCRE-FEEÏ LOI^IER FLRTEN COULEE DRM S 12'-T 152_RB6 RRER CRPRCTÏY q c{o 9

c¡¡ I / o I 7 (nJ , Ë. t = l-l=

I tÚÈ z. I o ilq / L¡SF J -_ b¡ /

,I + - RRER â E c, ¡ c,a t\ol 0.0 10.0 20.o 30.0 ß.o gl,0 æ.0 7O.O æ,0 90.0 1ül .o RRER TN RCRES

0 .0 ão .o 500.0 7lo "o 1000.0 Lão.o 1gl0,0 L76lJ.o m.o 22fi.o 2500.0 SRPRCTIY tN RCRE-FEET HRRTLRND DfiM 51 6 TL57 R86 flRER CRPRCIÏY C' a o)a 4/ -4= --t-

aa = C' ¡n - = o) (nJ E z. He I

I fJ o) I f lú =3 ('l l-r I (E tL¡ I J ,/ f!¡ q Þc, / s) + - RRER E G' ^ c,a o¡ o) 0.0 10.0 20.o 10.0 70.o sl.o flJ.o n.o æ.0 90.0 100.0 RRER tN RCRES

0 .0 100.0 Ðo.o $0.0 {00.0 500.0 600.0 700.0 800.0 900.0 1000.0 CRPRCITY TN RCRE-FEET RRNOLD COULEE DRM 51 T1s6 R86 RRER CRPRCIlY ai g,tl

ct¡ c¡ gt ¿ ct I¡ -1 I -g).< g-¡ aQ -å =E t¡I LJs= . ol l-t I tí8 rJ- @ Þ.< t!¡ / ué-Jer ¡\ / "/ @ r / ct a ct + RRER aþ - @ ^ cto ttt @ t 0.0 10.0 20.o I0.0 $.o fl.o dl.o 7fJ.o æ.0 gll.0 lf[¡ .0 RRER TN RCRES

0.0 æ/o.o $o.o d¡0.0 EI¡0.0 1fD0 .0 Læo .o 1,m.0 lm.o 1Em.0 2000.0 CRPRCTTY TN RCRE-FEET LONETREE TR I BUTRRY DRII s24-T 156-RB6 RRER CRPÊCIÏY ct a R ct ñ¡

c¡¡ !t. c¡¡\ .\¡

J (l-l c¡

=",. I r-¡zà ñl

I tÉ z. \¡ a I Fq

JäH L¡ I ct a // al c¡ o¡ {r RRER ï ¿lr c, a @ tn I (\¡ct 0.0 50.0 1f¡[¡.0 150.0 æg.o 25f¡.0 3fll.0 NRER TN NCRES

0.0 250.0 500.0 750.0 1000.0 1250.0 1500.0 CRPRCTTY TN RCRE-FEEÏ LO'{ER LONETREE COULEE DRI1 S 12-T 1 56_R85 RRER CRPRCTTY c, a t\tß

C' a rJ)ct gJ> -Q

=ú I z. td CJo @ ¡-l I I Êi8 / I¡- (o >¡d L¡ Ja L¡; t\ ,r .O / C' a r¡) +- RRER .ô 30 ¡!r

a u) ltt 't to 0.0 10.0 20.9 30.0 10.0 50.0 60.0 7g.o a¡.0 90.0 100.0 110.0 NREN tN NCRES

0.0 5fI¡.0 600.0 g)0.0 1200-0 ¡500.0 1800.0 2100.0 2+æ.o zloo.g 5q¡0.0 351¡0.0 CRPRCTTY TN RCRE-FEET APPENDIX C Preliminary Cost Estimate For Potential Dams TÀALE 12 - PRSLI!4TNÀRI COST ESTIüAÎE

Uppe.r Lowef,

Clearlng e Grubblng 2,V7o/A(Jre zlç 5,42Q 2.5/S 6.77s 31$ 8,130 3/S 8n130

SÈ.rippinq e spreêdlng Topsoil 59.26/ct 2,444/ç 635 2,300./ç 59g 4,060/ç 1'056 L7,4]9/ç 4,529 Excavåtion sL.e7/c1 5,600/S LO,472 3,6A0/ç 6,882 5,600/$ LA,472 L6,32O/ç 30,518

Enbånkmen,È 91. OOICY 44,92A/ç 44.92Q 43,.3L6/ç43,316 IOO,060,/S100.060 çt46,99O/s646,99O

Tlater for Conrpactlon 54"?2,/M GaL. 764/S 3,606 74O/ç 3.493 r,7O0/ç 8,024 ro,999/i 51,873

Pipe r24'r RCP 75/W *r30" RcP 95,/LF *r* 24í C!,tP 40.60/LF *2OO/S 15,00O *25O/ç 18,750 *330,/$ 2:4,73O *515,/$ 38, 625

Co¡rcrete 285/CY 34.5/ç e,833 47/S ]-3.395 73/ç 20,8A5 L06/5,30,21O Reinf,orcinq Steel $. soll,B 3,450/ç !,725 4t7AAt/Ê 2,350 7,3OO/S 3,650 10,600,/5 5,300

Rock Riprap 25lcv 60/S 1,500 60/ç tr,500 lt34o/ç 3,3,50o 6,200/9155,0OO

Rock Ritr)rap trílter Bedding L.2/Cv 2a/ç 24o zo/i 24O 670/1 8,040 3.100,1S 37.200

Seeding 259.77 /Acre 5/ç L,299 5,/ç 7,299 L5,/$ 3,897 201ç 5,195

Drawdôwn 16r DIP 32.5A/\E 052 052 1 31 Su'btotal I o2 99,650 30* contingency' Adrr¡inise¡ation t Engineering I 28,699 g 29,85O $ 67,301 I 306,438 Totå1 l24,4OO 129,5O0 291,000 L,321 ,899 Land 6,7OO 9,500 21,2QO 2f3.7OO 100

-c1- TABLE 12 - PRELIMINARY COST ESTIMÀTE (CONT.)

tlartland ÀrnoLd tonetree TrIb Lo$rer LoneÈlee Item/unit cos! ouantltv/cost Ouantitv,/cost Quantity/cost ouantitv/CosÈ clearing e Gr'úbbing 2,71O/Acte r/s 2,71o vç 2.7IO 6/S 16,260 Stripping & spreadinq ToPsoil s0.26lcY 6,O47/S r,572 6,94O/$ 1,84O 1,142/S 297 14,64r/S 3,807 Excavation çL .87 / cv e,28O/S L7,354 s,o4o/ç 9,425 2,27o/S 4,245 13,600/ç 25,432

Embanlments s I . 00,/cY 97,068/S 97,06A r]-7,27O/Srr7,27O r0,309./s10,309 377.130/$377,13O water for compaction 54.72/t'L GaL- r,650/S 7,7a8 I,994/ç 9,4r2 175/ç 826 6,Atr/s 30,260

Pipe r24" RCP 75/LP ri30" RcP 95lLF ùr* * ir*85/$ tr425/S 24F CMP 40.60/r_r. 245/ç L8,375 '* 360/ç 34.200 5,451 40t375 Concrete 2e5/cY s8ls 16, s30 77.5/ç 22,088 90/s 25,650 Reinforcing steel s.50,/LB s,800/s 2,900 7.750/ç 3,875 9r000,/S 4r500

Fock Riprap 25/cv r,640/ç 4r,0oo 80/s 2,000 40,/S 1,000 2,660/S 66,500

Rock Riprap Filter Bedding 12/cv e2o/ç 9,840 30/ç 360 Ls/ç 180 I,330,/S r5,960

Seed ing 259 .77 / rc/ç 2,598 Lo/$ 2,59A s/ç L,29e 20/ s 5, r.9s ^cre Drawdown 16" DIP 32 -6o/LF 25/S 1,31s 40/ç 2,LO4 20/ç t,os2 35/ç 1,84r subÈotal ç219,050 ç2O7 ,8A2 524,659 S612,910 30È contingency' Adminístration t Engineering 65,7 15 62,3LA 7,44L 183,890 Total 284 ,7 65 27O,2OO 32,100 796, 800 Iand 26,9OO 34,000 50, 500 92,5OO ÎoTAL COSÎ s311,665 s304,200 s82,600 s889, 3oO

t*t IncludeÊ cost for 24" cMP and $2'000 for an lnlet structure.

-c2- APPENDIX D

Individual Dam Location Maps ooNNYBROO|( ¡.3 rr.

22 23 Name: Aurelia Dam Location : 23-TI58N-R87I^I \'-l Sp.illway Capacity: I90 -r..i acre-feet

--2J-

(.

¿\ (. ) 27 26

a a a a L.t. lr tt rl rl il I I rl h J- I

t.t AURELIA a'I I ¡t ¡ 54 ¡¡55 J ¡ I Itt

-Dl- 3 I 3 Name: Fel Location: 6vr Spillway capacity:/ 280 AF I ...-...) I --t--I - +---L I )

( t 9 I o

I

.n. / -' / )

Name: Hartland. Dam Location: 16-Tl57N-R86W Spillway Capacity : 580

l6 t7 t5

)

ta=

----rræ-======ll + ¡ \ ¿ ¡ J ¡ I t I T I I I I I ¡ 22 zo I 42 I ¡ ¡ ll I \ I I ¡ (- I I I ¡ ¡ I ¡ I I : Upper Flaten Dam I I a ( I ¡ f tion: l5-T157N-R86Vü I ¡ I I ! Spillway Capacity: 930 AF I ¡ I I ¡ I t I

V2il. TO HARTLAIIO -D2- I

2

I (

)

t2

Name: Lowe 'i Flaten Dam I I Location:

I II S I irI h t" t4 t3

t_ I

I

-D3- CARPIO 5 MI.

a a þz'--_e= a a ="r.-"nn

ll tt rl ll -:-ærr=àa- tì.,

2

Name: Arnold Dam

I U Location : l-T156N-R86I\I Þ Spillway Capacity: 1306 acre-fee I í'--^

I J I I I

a--E

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