For P.el~a£e to PM's, October 28, 1959
RE:1ARKS BY GERALD M. KERR, RANG:'!: STAFF O~FICER, I:IBEAU Oz' UND NANAGEt-'12i:iT, T.: UTED S'!A':':?.S DL?t..1:.'if1E!I'! OF T~ :rnmr.:,:~n AT :IL....: Al.NUAL 1'1.E'.!::':w; O? 'I'HE UA'f!O?;AL REC:.A!~A'fION ASSOC!ATICN, DZNVi:R, COi.OBRJO, O~ OC70EER 28, 1959
It is a pleasure to par.tid.pate on this rr.eeting as a re~reser.tative of the Bur?.<l,! of La!,d !>f-?.:J.ai-<>mE>~l:, D-.~1-:a:rt:.-ent c= t~e Intericr, to discuss t~1e ~ate-:shed m~!lag<:.m-=:;,.: ?roe::.·r.1.il' cf. the Bur2.au. It :i.s s Lgr.i.f~ ca:1t thnt the vccant public d.:.uA ~r. J.c.1.:10.3 a::i•i t.he;.r re~.ation to wa':~rs!:1ed pro~iems ht2.r~ in the West be cor.~:.clered ir.. t.h':! total picture of watershed
manip1lnt:l..o:1.
Tb2 l:0!·£11 ,E:::a of v~~.1111: '.1.1reaerve:1 r,ub1..ic lands rl;!m.'.l.in:f.ng today in the Ur.ited S::ate.B, excJ.u3J.ve cf AJ.eer<a, is ai=:?rmdmately 170 m).llion acres. This e.i_ee. d:ies fi::,t iP.c1_•Jde uc:d.onaJ for~srs, n:i:..im:a). parks, wil.dJ.:i.fe
res"!rv.:i.tionR, m:.lt~nry :?,.1d at.tier resP.rvat.ions. Eo\.v~·.r?.:"."~ i.n addition to the 17(; re~l:i..i.oc1 acre&, th3r~ a~e ai:-·prox:.mately 17 f'.'.i.J.l~on acres of ·~cblic dom".i:i lands i:n various llJi thdrB.val cc?tegor:~es inr::'..u::iing recJ.a[Pc.t5.0n, pcwer sii:e1J, or ;.u!:Jlic \h1t:e~: .1.~.-:2·:·J~s, whi.:::h are a:.so rr.a::.ci.geJ by tl!~ i:!LM, br::.np.i.):ig ti:e t0tal a.i:-ea e~'.r.iniet.?~ed by th.: B~..11 to :i.i>l'roxima~ely 187 II!iili:m acres.
The bulk of these pt'hli.c do;11a:l.n la.:11s 5.a loc.lJ.t"'!d in the Western
States arui ts erobie~e~ w~t~~n f~szing d~Pt=icts e~tabliahed u~ler the
provL~ions of th~ '.Caylor G.:a~iug Act. '.Lr1.i=;·c~ is, l1•)wev':!r, a coc~.siderci.ble acresg~ con~iGting of scatter~d :i.2clnted ~~arts tb~oughcut the Western U.1itGd Sta.t':!S. We ai::~nir::~at-.er 2~proxi wa.·,:e:.J.y 2~ r!n.llic,r. ::i.cres cf tim!)ered lanes J.oc:1Led in fotast d1stri.c.f:e iG v;~<Jts.~~n ~.:egon co:isist:i.ng of Oregon a:-1d Ce'!.ifornia re-.restP.,i L:11d8 cornn:::;::1ly '?:"'':Aned t0 cs r.h=
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lands. W'ixn tl~e exce!)tion of t!,<:sl;! 1>J~~.:1lled Cf·': :1.::-n)c :i.r.. C':.e.r;~n, and. sca~.:eredti:nbP.r lan'.il? in oth~r r.,ul:-:!.ic ,:l.o:w.i:.1 S: :i:~.c s, t• 1csc r.•1bl:i.c J.a::ida arP-clc:.sse:l as :-,er.::.i.ar:td an'.1 ".lrc US'i'C r .:irn'.1.0:i ly
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e~~a::i.ng. The wate:cshed m~n..agemi:?nt practice or. i:i. ... e<Je l,:;.i::~~r ty_.les cf ?t·.i:,\ic coma.in lands is the sul::j,.:ct of my clis:.nssion Leri: t0~e.y,The average e.n~l'.1al ra.infall in these rublir. land aree.s varies £.:om about 5 to 20 in~~.e3. W,-:tt'!.r yielc3 are l,'f·,, ra:1?,n~g b~~-.:P.<:n 1/10 to 5/10 inc'L1es, th~ a·vcrag~ bei.r .. g ab,:,:1t 4/10 i.:.1.ctl~s, lit.1i:1t:b. is a!)7"::'ox:!.mately 3
perc~nt of the aver3.g,:, a.cnuAJ. rr,·:c:·~1,~:;.~.'lt.j_·:.!1. Tt1~ s m.:bJ?.Ct c,f '-".t?.r yield £5.gt~re is based en recon:o :'.:rcti'. 2t::e;:1.ill fl.o.-J gaug--.8 that are lc:;co.~ec on ruain drai~agec whic~ g~L~rally <:')VP.~ an a=e~ ssve~al to~n~h:rs in size. Be~a .. ~se of t,n lirrn.·:::ed i::u·:.f.ac'! c:>v:ra3e ,J:f. pr~~i'!=:i.t:,t:icn iron, h;.gh inte11.si.ty cu1::;.1er .:a:i.ns::0n:1r.;, t~1~ r,~rr.~L~t::ige. of p:.:-ec.i;,i.:at:Lo!l t!:at will run off from a t:o.:·ih•.11:.?:.:-y of ;:·.;~ cl.raina:;~ .s.r~a l:a~ b~en known to be gre-:ter than that reco;:-~.sd at tl,~ gaug~.ug stat:!.on.
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This makes hydrology for small t·1atersheds one of our most difficult problems. Although weter yields are comparetively V;.ry k,~.1, t::e floods
that do occur cause excessive erosion and in ffiany cases sericus property damage, and even the loss of life.
Evapotranspiration ranges bet:ween 25 inches in the north to 55 inches
and mo4e in southern A~izona. The average is about 27 inches. Low water
yields are explained by the high evapotranspiration of 27 inches on average ~recipitation of 11 inches. Precipitation that does not
immediately run off or evaporates from the ground surface will percolate into the soil and replenish the soil water supply with any excess going
into the subaurface streams or reservoirs. From an annual basis it appears that we don't have a lot of water to manage, but in terms of high intensity storms with SO-year frequencies or more, our water managem':!nt problems are quite complex. 'i'h~ soil porticles and debris transported by the storm flows add to the complex:i.ty of the problem. 1'he estimated sediment production will range from one tenth of one acr1::-£oot to as much as 3 acre-feet per square mile per year.
At the present time there is a great deal of interest in the South-west to increase the yieid oi water from a given unit of area.
Experimental work is presently being conducted by the Forest Service, Agricultural Research Service and the Geological Survey to determine the possibility of increasing water yield. The tests are centered around the manipulation of the vegetal cover for greatest water yield without
adversely affecting the watershed conditions.
In order to apply an intelligent program of watershed management, these millions of acres have been subdivided into approximately 650 community watersheds, varying in size from a few thousand to more than a million acres. In turn, the community watersheds are grouped into 42 major river subbasins comprising 9 hydrological regions or river basins.
Wctershed planning for public lands follows three levels of area and intensity. Long-range plans have been developed for all public lands in the 42 major subbasins. Originally these plans were prepared on a 20-year basis with provision for the total watershed protection and improve-ment requireimprove-ment. Provision also was made for pe~iodic revision of the plans at 5-year intervals for the purpose of refining the estimates of conservation needs and to keep the plans on a current basis. These
plans are used in determining the priority order of community watershed and in preparing annual program planning estimates. The second level of
planning is in the form of a gener~l community watershed plan, and the third level is the detailed watershed plan prepared for either a segment of or the entire community waters~ed.
All lands managed by BLM are included in community watersheds for which conservation needs are being planned in general and in detail. The Bureau's principal priority criteria is based on the erosion and water
One of the first management tools to be applied in a watershed program is that of managing uee of forage resources to conforw with the productive capacity so that the major causes of erosio,1 and unnt~cessary disturbances of the soil surface can be controlled. The general objective of the program as a?plied to t~e public lands is to maintain the watershed in a good condition from tte standpoint of vegetal cover so that the land area in a drainage basin will withstand very high··intensi ty storms with a min:Lmum of damage. As a general rule, water control structures are designed to control runoff water from storms of 50-year freq~~ncy. Exceptions ar~ made wh~n downstream safety of life and property are
factors, in which case the design is based on a 100-year storm frequency. Good rar:ze conditions can generally be maintained by regulated use, but in the event. the allowed use is inadequate to restore the desired
condition of the vegeta.tion and halt serious erosion, a program of land and structural trea<::ment is clt>J?lied. Another objective, therefore, is to derive the largest volume of varied land uses from the watershed, yet promote the maximum sus~ained level of productivity in relation to
c~pability of the land. It is estimated that forage production under proper ma,1ag2ment of use., supported with treatment and si::ructur::11 practices, can be increased 270 percent.
Most of the Bureau's conservation work is in th2 nature of upstream or headwater treatment. He plan, design, and construct wate:::- man,::.gement stLuctures for water control and provide methods to release wa~er to downstream t.se that ccrmot be used to increase forage production and which is not required for livestock and wildlife.
With respect to water rights, it is Depcrtmental and Bureau policy to con::orm with State laws. Filings under State law are made whe!~e. co11si.mr;tive use of we.te'!:' is ir!volved. Infring~rcent on existing rights is a\7oided. Many of the si:ructures in our wate:,:-s:1ed management plans are desig.1e<! to slow down water flmo1s, that is, to "walk" the water off the land rather than to allow it to run unchecked as a destructive erosion force. Detention dares placed along the intermittent flood
channels or arroyos are intended to reduce peak flows. Draw down outlet structures are installed in the dams to lirn:.t discharge end extend the reduced flow over a longer period of time. These detention dams are not intended as impoundments. Their primary purpose is erosion co~trol. Beneficial results extend to downstream lan1s and facilities by reduction of sediment and silt deposits in ir:ipoundrnents and other structures.
Before works of improvement are undertaken by the Bureau, a field investigation is made to determine rnnge conditions and erosion problems; field data are analyzed and local O!'ganizations and land.owners consulted; a work plan is devised to offset influences adversely affecting the
St3bility of the watershed, after which structural practices a~d land treatment measures are applied, closely coordinated with the forage resource use.
The conservation of land resources is not a Federal monopoly.
Therefore, an il:lp!'n:tant landmark in the history of conservation legislation
was established when the Watershed Protection and Flood Prevention Act,
(Public Law 566) was passed, whic.h places full responsibility on local
communities for initiating small watershed projects. F~r the first time,
under this Act, the importance of upper water shed treatment as a logical
starting point in our flood control and water concervation policy was
recognized. The law also recognizes that the watershed is the most
logical geographic unit for attacking the problem of conserving our soil and water resou~ces.
Under this Act the Secretary of Agriculture is vested with the
authority of giving technical and finand.al aid to local communities who
act through their own organizations in planning and carrying out works
of improvement. Agrict,lture is Soil Conservation Service has the primary
responsibility for carrying out the provisions of Public Law 566. When
public lands are invol~cd the Bureau of Land Man~gement works closely
with local people, State and Federal agencies, in rlanaing the watershed
program t•.nd.e.r provisions of Pvulic Law 566. Th:-oug':.1 a financial
arrange-ment between the Departarrange-ment of Agriculture and the Departarrange-ment of the
Interior, funcl.s which hcve been appropriated for watershed developmant
work can be allocated to the Bureau of L,md Managemer.t in the amount planned and approved for d~tailed planning and project construction on public lands.
To <late, the Bureau is co0perating in six small watershed programs
which have been planned and approved. Among the cooperators in the
Bur~au's small waters~ed progra~ are the soil conservation districts,
which in most States, have aut~ority to sponsor such programs.
In recent years a pilot soil conservation district program has been inaugurated in each of the Western States, where emphasis has been placed on range revegetation measures, water development and control structures and land treatment practices wh::l.ch will retain the soil and water in place aud provide an increased amount of native or introduced vegetation. We have found that an import~nt land tre<.ltment practice is protection
fencing to control livestock and preserve treated areas. These pilot
stu<l.y areas have been used to advantage in formulating general cooperative procedures for use on other areas.
The Bureau of Land Management in order to maintain vigilance in keeping abreast with new and better ways of conserving the productivity of the public lands, also cooperates with other Federal egencies and land grant colleges engaged in research ur,dertakings. A series of
research studies on erosion, runo=f and sedimentation is being conducted in cooperation with variovs agencies in the Southwest, particuL:rly in
Arizona. The Geological Survey is collecting hydrological data to be used
in watershed planning and has recently estimated that phreatophytes cover
water annually. The Agricultural Research Service is complet~ng evaluation st~dies on the efficiency of detention dams in trapping silt. In ~-7yoming, in cooperation with the Agricultural Experiment Station, the effect of gra~ing and conservation measures in community
watersheds is being evaluated. The correlation of data collected provides
the information needed for the successful planning and development of water
shed programs, and the practices carried out under the small watershed
program contribute either directly or indirectly to soil stabilization,
water conservation, and other eopects of watershed protection.
You can readily see from my brief description of our watershed
program that it is not in itself an indepe::id:ant entity, out its success
depends upon its coordination with cthsr prog~ams including those of the
Bureau of Reclamation, So:i.l Conservation Service, Forest Service, State
water conservation p~ograms and others. Only through cooperation can the over-all objectives of watershed manipulation be achieved.
