Phillips Addition-CS 860722 Coppe~:. Texas 7504 g
f'--~/.,..'" /~,-------~,, The City With A Beautiful Future 2~.4- 462-90~0
MEMORANDUM
July 22, 1986
TO: Dale Jackson, Chief Building Inspector
FROM: Linda Varonich, Community Codes Inspector
RE: Complaint Investigation, North of Phillips
Based upon a request from Steve Goram relaying a concern of Councilman Tom Morton,
I did not observe stagnant water conditions in the tract of land between Denton Creek
and the General Homes subdivision bordered by Phillips. Some construction debris is
beginning to blow or be deposited onto that wetland area, but I do not consider the area
in violation of Ordinance No. ZS1 any more than ponds or reservoirs constructed to
hold back water in other areas of Coppell.
Attached for your information are several pages reprinted from the Sanitarian's Handbook
that deal with mosquito abatement. Some engineering concepts concerning various
drainage methods are outlined specifically as a means of controlling breeding areas
where water may stand longer than one or two days.
LSV/dgc
1977 EDITION
Fourth Edition
SANITARIAN~J HANDBOOK
Theory and AdmlniRtrative Practice
for
Environmental Health
Ben Freedman, M.D., M.P.H.
Public Health Consultant,
Professor of Public Health Administration.
School of Public Health stol Tropical Medicine
~ U~v~rsay
PEERLESS PUBT-IRWfNG CO.
P.O. Box ~0187
New' Orleans, l.a. ~l~0 l;..~_...A.
FUN-DAMENTALS OF MO/~QU~ ABATEMENT population miy multiply to a much grmter exte~ ~,~, -'~'--/
Considering the great diversity in types of breeding pt~lator~ had been diminished. Therefore, · contia~_~.
places, types of food preferred, flight habits, ability to of larviciding is important to maintain mosquito ~
transmit disease, and economic ~ffect of the various spe- The lesson is, that every control measure, because it
cies of mosquitoes, we begin to realize the complexity of sets. so?e phase..of n~.tural b.a~..c~., ~ withia it ~;..
the problem of control. Generaliz~ rules of thumb are not see~s o~ an opposite outcome. It ~s this that must be ~
to be too closely followed, but certain definite simple rules ly watched. And it is for this reason that the use of DIY~
can be apphed ~y the sanitarian with rather good results in and other techniques, which upset natural bala~,
instances where the problem is not too extensive or com- should be strictly supervised by experts.
plex. Success in mosquito abatement depends upon exact Attention is directed to the use of naturalistic coatr~
knowledge of the species of mosquitoes in the particular methods which aim to effect simple changes in envir~.
region to be placed under control, of the habi~ of each par- ment to make it unsuitable for the breeding of the pattie.
ticular species or sub-species, ~nd of the appropriate meth-
ular species in that region. The naturalistic methods ar~
ods for abatement of each species, most instances of an engineering nature and require ~
Up to tbe time of discovery of DDT, screening, frequent skRled personnel as directors of the work. Th-ere is~'~
spraying, and use of repellante was a difficult and certain- dence that these methods will in the future become
ly a tedious method of adult moequi~o control. This meth- used and developed, since they lend themselves to ~
od was therefore not considered a prlms~y activity for scale projects for mosquito control. There is little douh~
large scale, permanent control, but only an accessory that the future will soe mosquito control projects
method and one used in emergency situations and in un- magnitude is today scarcely ims~o/nable. Let it
developed areas. Larva control by mechsnlcal, naturalla, understood that naturalistic methods are etill in the
tic, and toxic [arvicidinff procedur~ w~s the pr/m~ey perimental stage, but that they hold one of the pm '.n~si~
method of controlling mosquitoes. DDT has, to a large ex- solutions for perm=~ent large scale mosquito control.
tent, changed the relationof the above primary and acces- the presence of a mosquito tr~n-mitted d/sease a selectiv~
sorv methods of control. The masons for the change are attack {species sanitationl against the vector species is
that DDT and other synthetic insecticides: primary importance, especially where lira/ted funds maim
1~ Are cheaper than other mosquito poisons, it impractical to attempt a program for the abatement
2! Have the property of leaving residual toxicity that all types of mosquito breeding. This method, together
may last for months when sprayed on surfaces, with the use of biological tecb_niques such as are possible
3~ Can be applied to surfaces without staining or with insect hormones, anti-hormones, and pheromone~
streaking. Isee chapter on Insect Control} give perspectives of a good
4) Are effective killers of the adult as well az the lar- future in selective insec~ control.
val forms. Ideally. reducing the production of mosquitoes is prin-
5) .Are excel!en: means for rapid elim/nation of dis- cipally a matter of reducing, safeguarding, or eliminating
eases ca_~r.;ed by mo~qu£toes, the water in which mosquitoes breed, or by appropriat~
Because it can. be used so effectively against the adult naturalistic methods, rendering such water unsuitable for
mosquito, adu!ticidmg or imagocid/ng has come into mosquito breeding. If. after this has been accomplished to
prominence as a prim~- method in preventing and con- the greatest practical~xtent, there still remains some mos-
trolling diseases ca.wied by the mosquito. This change of quito breeding, then this residual production must be con-
emphasis may even become greater when newer chemicals trolled by supplemental measures. But the use of larvi-
with greater toxicity and ]ess resistance-producing quality '
cides for the destruction of the aquatic stages of mosquito
for the mosquno are discovered and having greater ability life must always be looked upon as an accessory method o!
to produce residual toxicity and being low in toxicity for mosquito elimination, the necessity for which should be re-
man and animals, duced to a minimum by the primary methods of drain ~a~t~
A word of caution: lest we go to extremes and forget the filling, constant level flooding, controlled reflooding, an
importance of the perms,~ent control methods effected by various biological methods mentioned above. But these
mechanical and naturalistic pmctice~__, permanent large accessory methods are by force of necessity, still being
scale mosquito control must utilize all proven methods used as primsry methods due to purely economic reason~
that reduce larval and adult populations most effectively and needs for rapid d/sease elimination. There are se many
and economically in long-time program=. Over a long peri. communities in our country which are too poor to make
od, the mechanical and naturalistic methods are cheap and outlay of money at one time that would be sufficient to
effective, do not exact tedious detailed attention to in- carry on a control program by the primary methods.
dJvidual abodes, and do not contribute to ~langerous poi- the fact remains that we are not far off from the day whe~
lution of our streams and soft as do the newer chemical the primary methods will be used for permanent control.
usages. Perfection of detail and continuity of effort are i~
There are certain pit-falls which must be kept in mind in portant in effective control work. A sustained attack.
the development of techniques which produce modifica, after year will produce better ultimate results than in i~-
tions in the natural environment. The most important to tense attack in one year followed by comparative negte~
remember is that. in the struggle for survival among all and inaction.
liv;.n~ organ:sm; in the natural state, a balance develops
b~e~n ~h~-,~r~r:~m<m- and thmr enxironmenr which helps
them survive the forces which would completely destroy PRELIMINARIES TO ABATEMENT PROCEDURES
them. For example: The number of mosquitoes in var/ous ·
areas would mukiplv to an unbearable extent, so far as hu- Before any mosquito abatement project is begun_, _~
mans are concerned; if certain aspects of the physical eh- must be planned and organized. The proper .pers~_. ,_.n;~
vironment became so favorable that all mosquito eggs de- provided.sh°uld be Thisengagedis theandidealadequateand logicalequipmentmethodantlofSUpp~'
veloped into aduks, or if certsm mosquito larva predators dure. But in the "rough and ready" activity of eve~_:.~d~
such as Dv'.iscid beetle larva and the "back swUnmer"
would not Be present to de~tmy th~ mo~luito larvae. DDT
work. where adequam personm~ and money are um
. lacking, and where emergencise arise that require,
kills not only the mosquito iar~'ae, but also the above men-
tioned and other predators of the mosqOito larvae. Then. mediate action, these preliminaries am by.pas.s~! .aa~.~.
after the affect of the DDT has diaappsand, the mosquito work is begun on a more or less trial and error basiz, ~
1016
~'.-.~ o the effectiveness of the oki iIt,~ld-by cure-~l ~ ~ w~h w~ m~ wa~ when ~he ~t of ~ ~ ~ : '- -
~ of o~g. ~g ~d ~. A~ ~t ~t ~ ~ or ~h ~t~ns ~'h~h w~l p~vent ~mp~m ~. - ....
_~d t~t t~ meth~s ~ ~ a ~ n~ of m- ~y a surfeit n~ of &~s shoed ~ ~ ~ ~. ' -
~'~ We ~ults ~ ~y ~ on. It would ~ ~mp~h the ~s~ pu~se, that m, ~ ~ of .....
~,,,~o contel pm~s. T~ few dishes w~l f~ ~ att~n these obj~tiv~ w~
~"~he p~l~ma~, re~ shoed ~dude ~ta ~d ~m- many w~l inc~ase the cost of construction a~ ~
mendations on the foUow~g ma~: nance.
1~ The ~es of the ~n w~h shoed ~ ~- Gene~y, ~ ~hes should be const~ ~ ~w
c,u~e~, ~ '~ within the pro~t.. ~ttoms, smith sloping side~. ~th as f~ ~ ~ ~
.~ Fopulat~on. a~a. ~nd ~ v~uat~on of the ~- sible, and without sha~ turns. Usua~y the si~ of
ditches ~hould have a s]o~ of about 45: althou~ ~
~'~ ~, Location and area of the p~cip~ b~g places, mud or sand the slope should be flatter, wh~e ~ ~ or
4~ Tentative suggestions ~ ~ the ~st methods of clay the sides may ~ nearly per~nd~cul~. If ~h~
wnt~l for each p~ncip~ br~ ~. built at ~ angle to the slope of a hi~. the up~ side shoed
5~ The s~ies of mosqui~ ~voiv~, wkh a b~ef
&~sion of the~ b~ habit. ~ somewhat flat~ t~n the lower ~ o~er ~ ~n e~
~) The ~o~t ~d ~'~s of dom~tic mosqui~ b~- sion. The bottom of ~ dishes should ~ U.sha~, ~ V-
xg with~ the ~on. and m~ for a~ment, sha~, ~d ~ the ~e of ~de ditches the ~t~m sh~d
TI The p~bable or~n~ation that would ~ ~u~, slo~ ~w~d the ~nmr even if the sides ~ ve~. As f~ ' -
~cludmg ~r~el and ~uipment. ~ p~ctic~ aH vegetation w~ch would shelt~ the ~t
mosqui~ should ~ remov~ ~om the ~ of the ~.
8) ~ pre~ ~tima~ of ~st, ~ for ~- The mai. ~h shou~ ~ ~nst~c~ ~t ~d
~ent work ~d for ~ ~~: ~d ~m~- ~st~ o~y w~n ~d whe~ they ~ ~~. At
~e ~ for ~ of ~il~ s~e ~ ~tio~.
9) ~e ~c lo~z ~u~ by ~s~ ~ t~ t~ it my ~ ~t ~ w~t ~t~ ~ a ~
~ ~d the ~c ~v~ w~ch wo~d ~t ~m h~ s~w~ ~ d~i-e the n~ ~ 1~ of
' ~tio~ or h~ ~h~. A h~ or b~ch ~ shoed
~m abaft m~. ]o~ the m~ ~h at ~ ~um ~gle or gen~e c~e
o~er ~ avoid the de~sition of deb~ or s~t at t~ j~c-
METHODS OF ~ATEMENT tion. or ~ p~vent erosion of the op~si~ b~ ~d the
fo~ation of holes ~ which water may ~ m~.
~a~age ~d Filling C~e should ~ exerc~s~ tha~ the d~ t~o~ ~t ~ dig-
The A~: (a~ To d~ ~ excess s~ water in~ ~ng the ditch d~ not fo~ spoil b~s whi~. by p~-
&tc)~es within a day or two fo~ow~ ~s. {b~ to prevent venting the ~age of su~ace water in~ the &ich.
the ~o~ation of any ~nds, ~ls or pud&es ~om rems- c~ate ~ls and puddles ~n which mosqui~ w~ b~.
Where the dish ~ns transversely ~ the slo~ of the
~g more th~ a day or two foHow~g r~ns. ~cl ~ ~move
~] wa:er from the area t~ be p~t~t~ wit~n seven days ~ound. the excavat~ d~ should be plac~ on the do~-
' h~l side. Where n~essa~', sooii ba~s shoed be ievel~ or
fo:~o'*':ng a ram. ~d: a~.~ :,~ accomplish :he above in a prac-
uic~ and ~onom:ca! m~ner. Where the a~ cannot ~ :he d~n d~spes~ of e~se~'here.
~c~ev~ completely, it ~s n~ess~' ~ at.rapt ~ ~u~ Whe~ :he &~ch goes t~ough a culve~ or wherever a
the br~ing ar~s m the po~t wh~ other ~ntrol m~- pi~ ~tion is ms~ed, the ~ade should ~ m~
su~s may be f~sib]y supplement, prevent ~demn~ with the flow of de.sits of deb~. At
An~imosqui~ ~ainage may be accomplish~ by m~z the downstre~ end of the pi~ or culve~, the ~t~m of
of su~ace ~tches of either the u~n~. ~. or ~k ~ :he ditch should ~ 1~ with stone or ~ncrem for a ~s-
~e. or by subsu~ace t~e ~a~. ~ce sufficient ~ prevent erosion ~d the fo~ation of a
' ' hole in the bottom of the ~ch. The up~r end of the
In pl~ning a drainage system, consideration should ~ or culvert may. ff n~ess~, ~ sc~n~ ~h ~n rods or
Wen ~ ~he probable ~od du~ w~ch ~he dishes w~ a w~en ~tmg m prevent ~he entr~ of l~ge pi~ea of
contain water ~d to the ~st l~ation of the &~hes or tile deb~ or floa~.
~es with mg~ ~ ~ade and the ty~ of ~fl. C~e~l ~~ may ~ u~ m an adv~ ~ w~ ~und
pla~ing for. ~d su~ision of. the ~nstm~ion of a the ~nst~ion of ~r~ ~hes of co~ide~Me len~
~age sysmm will ~ its eff~tiven~s ~d ~u~ where th~ ~ su~ient f~ ~d volume of flow ~ ~t
the cost of ~m~na~e. of ~ti~ ~ ~ade. T~ m~hod ~ most ~able for
In many ~ces it ~ ~ found des~able ~ make a ~g sw~ps ~d m~hes where the soft ~ waC-
map or sketch of ~he ~ m be d~, show~g the i~- ~ak~ ~d whe~ them ~ m~y su~a~ and zubsu~a~
~ion ~d available ~ade of at l~t the m~ ~hes or obsrmct~ns, such ~ r~ts and b~sh.
subsurface ~a~. Dynamite cartridges are plac~ m holes made in the
~o dit~es: In or~r ~ prevent mos~ito breed~ ~ ~ound with an ~on bar or a w~den ~le. The s~e of the
~he water ~ ~hes. o~n ~tches should~ ~tru~d dyn~ite ch~ ~d the spacing and depth of the hol~
~hat s~and~g wa~er ~ be ~mple~ly removed ~d sm~ de.nd upon the width and depth of the des~ ditch
water dram~ ~om the su~a~ of the ~und ~d ~m the nature of the ~und. and am usury de~ by
· tches within a short time afmr a sto~. The ~de ~d cfi~ shots. In the ~nstmction of the o~ dish the
width of the dishes .should ~ such that w~le ~ water ch~ges are plac~ a~ut 24 roches ap~ and at a depth of
about 24 ~nches. L'su~Iv a s~tion lc~ or mo~ f~t m
wi~ be c~ied away, the velocity w~ not ~ sufficient ~ -
produce "~tholes" by erosion of the ~ttom or sides of len~h ~ excavar.~ at one finng. It is usury n~ess~
unlined ~hes. Such ~tholes ~y con.in wa~ long smooth the walls and ~trom sufficiently to remove the
after the retarder of the dish b ~- ~d constitu~ ~gh ~d low s~ w~ch would ~use the fo~ation of
places for pmhfic mosquiw b~ing. A ditch that ~ ~ ~ols.
wide or ~ fiat may i~ewme mt~ wa~er ~ sm~ dep~- Ditch digg~g with dyna~te, where practi~ble,
s~ons and thus defeat the pu~ of ~a~a~. U~ezs ~pid and ~onomic~, and has the ~unher advan~ge
~ ~m~ by ~nt a~ ~ ms~ d~ the d~ which would o~he~'i~ fo~ s~fl bahia ~ ~-
~nst~i~. ~m~ of the dish may ~ ex~va~ ~ t~bu~ ov~ the te~. It ~ ~t a f~ ~ for
~w or a~ve t~ ~b~ ~, p~uc~ ~ ~w ~ ~' ~fls or m t~ const~ction of sm~ &~ or
during the we ~on/~ too gl~t to b~ ~ by the orttg
~ ~. Whe~ ~ o~. .~ ~ ~ ~ 1~ ~fl ~' tile drain~. T~ ~ ~ ~ ~s of
ort~wh~m ~d~sides ~ such~y~ ~h~i~y~~.a h~hinc~asi~gVel~itv. ~tch on the ~tWm of ~h 6 ~ 8 m~ t~ is ~d ~
~ ~ ~ ~ ~ ~~ ~ d~ the ~u~i m~. I~ ~ ~~ ~-~g ~e ~h,
eff~tive~ of the ditch in p~vent~g mosquito bring, o~ina~- s~tion~. ~n~ ~ linings ~e ~id on ~p
Under th~ c~ms~ it may be found advisable w or immediately a~ve the t~g. The ~ weather flow
line the dish with ~me ~m, ious ma~ for the p~- carri~ by the tile ~ w~ ~e wg weather flow
~ of ~vent~g erosion of the sid~ ~d ~t~m or ~v- drained away t~ugh ~ the tRe ~ and the su~.
mg of t~ bn~s. A weH-~n~ru~d ling al~ facilitaces imp,~sed open. conc~te 1~ dish.
clea~ng, i~e Fig. 1~
Ditch~ may ~ lin~ with conc~te or with stones laid in Intercepting dra~s. ~io~y subs~ace tile
mom~, preferably cement molar. Usury a linLng which are mstall~ for the p~ of intercepting the flo - of
covers the ~tWm ~d extends up the sides m a~ut th~ ~page water. ~p~e w~ ~ ~d water fsp~g
~ches a~ve the no~ wa~r ~e w~ su~ ~d it is not ter~ which is fo~ ~ t~ s~ of the ~und by the
n~ess~ ~ ex. nd the ~ m the Wp of the dish w~s. sit/on of the underly~g ~us strata. S~ ~
At other ~, o~y t~ ~es, t~, ~d junc~o~ n~ usually ~cur on the side of a ~ but may ~ found ~
~ ~- I~alk~es. The s~pa~ wa~ u~y coU~ts in sm~l ~h
At sh~ c~es the ~ of the ou~r w~ should ~ or puddles or p~u~s a ~hy ~ ~ which mosqui~
r~sed h~h enough to prevent ~ou~g by ~ ore.ow of may br~d in large num~m. An ~epci~ dr~n whic~
sto~ wa~. ~ w~m the c~nt ~m a brach ~tch cons/scs ora r~e li~ cov~ with ~d~ ~ ~ l~d at
st~es the op~ite si~ of the ~ ~t~, the ~h lining prox~ately ~hr ~les W t~ ~ion of flow of t~
~y ~ ~ or a sp~h w~ ~ ~ p~ent ems~n ~page water. It shoed ~ l~ a~ve the ~t of
of the e~h ~d the lo--lion of ~t~l~. max~um flow of the ~ ou~p as ~~ by
If s~n~ ~ u~ f~ li~in~, f~ly ~e ~t s~nm s~tion du~ or ~n ~r a h~ ~.
should ~ ~1~ for t~ p~. ~ ~~ shoed
~ ~ with s~ p~ ~d ~e ho~ ~ ~th ~ Mainten~ of subs~a~ ~. We~ ~nst~
~t mo~. subsudace drams ~qu~ but Uttle at~ntion, although
casional ins~tions should ~ made for clog~g, h may
Subsudace ~e. Subsuda~ or sub~fl dr~na~ ~ n~essa~, to provide pm~tion where traffic pass~
lines consist~g of cove~ g~es or rock ~ dishes may over a rile line. Ord~a~y no clewing or ~ading is re.
~ used w ~, away sudace water as it is absorbed inw quired.
the ~ound ~o lower the level of the ~o~d water so that Resume of p~nciples of ~inage to ~ followed:
the sou w~ more ready ab~rb the surface wa~r, or ~ a~ Drama~ systems should ~ pm~rly designM by
~rcept seepa~ pl~es ~d prevent ~epage water ~om mosqui~ control en~n~rs w ob~n maxum eff~t with
form~g ~[s on ~he s~face of the ~ound. minimum work a~ mi~um cost.
b) Grades must ~ us~ w best adv~tages and must
TRe drayage. The t~mg us~ v~es ~ s~e ~om 3 ~o 12 b~, e', en to a~ oid fo~ation of ~kets or potholes.
roches, usually ~om 4 w 6 inches. ~ E~eter. The lines c~ Cro~s-~'uons shoed be ~ nar~w as possible con-
are laid m the generE d~tion of the ~ade ~d ~om 50 ~o sisten~ ~ i~ h necessao' capacity, and sid~ should ~e prop-
~ i.O ~ apa~. The a~'er~e depth of ~he t~g is ~om 2 to eriy
4 roches ~low the s~fa~, but the depth at w~ch ~he :~e d~ Laterals should jo~ m~ ~hes at same level,
~ laid and the d~ce ~tween ~es w~ v~y ~or~ same grade, and at an acu~ a~le.
w the ~aphy ~d other 1~ ~n~tions. The closer a e~ Culve~s and pi~s should ~ c~e~y laid ~o exact
subsurface dra~ is ~ the suflace oi the ~und, the mo~ ~ade. and prot~t~ ~ ax'oid formation of potholes at
rapidly it will ~ain away the s~face wa~r and the smaller ends.
the ~ea which it w~ ~in. f) Excavat~ di~ shoed be sp~ad or the s~fl ba~
The tiles are Ired m ~e ~t~m of a ~y ~ad~ cut t~ough to avoid obs~ct~g wa~r t~g ~ en~r the
trench the slo~ of whch shoed ~ ~t l~s th~ 3 inch~ ~h.
~r 1~ f~t. The t~nch ~ ~ ~ ~d the tfl~g g) Cleaning, cl~g~d~bb~gsho~dbe~
~ver~ ~gh ~h, ~vel or ~ad~ ~k. Gravel or a widgh ~ ~t pm~r ~ion of ~h ~d NO
~d~ ~k ~llin~ fac~ ~e rapid ~ov~ of s~ WIDER.
wa~r. If ~d~ ~ ~ u~, the 1~ s~ ~ pla~ ~ hi Conc~ dish l~g is v~uable ~ ~1} pmvent~g
the ~t~m of ~e ~tch ~und ~e tR~ and the fin~ erosion ~ ~th sides ~d ~tmms. 12~ proving p~'
~ad~ at ~e ~p. T~ ~g s~d ~ ~ m a he~ht ~nently and pm~rly ~d~ ~t~, ~d ~3~ ~uy
of ~ve~ ~ch~ a~e the 1~ of the ~und. ]ower~g mainmnan~ costs. Des~ of such work should
~ by a mosquito control en~n~r.
R~k-fill~ ditches ~thout tRing. Subs~ace drainage i~ Sufficiem ma~enance should be ~ on so
may be accompUsh~ by ~nches back f~l~ with ~aded at ~1 t~es the work fulf~s the pu~ose. Th~ is essenti~Y
r~. or relatively large s~nes but without ~g. The t~ province of the ~i~.
trenches a~ usu~ly dug ~m 12 ~ 24 inches in depth ~d j) It is the smaR de~s w~ch may mean success or
the width of the spade or show u~ ~ dig~ng. The ~k fa~ure. Meticulous attention to de~ is es~nti~.
us~ for fRling should ~ ~om 2 ~ 6 ~ches in dmmeter
~d. if ~ad~. ~he l~r s~ shoed ~ plac~ on ~he bot- Filling.
tom. a' Low areas may ~ entirely fiIied, or
Rock-fill~ dkches of this ty~ ~ suitable for draining b~ F':Ued to a ~e~ el ~rmkting drainage.
away slowly acc~ating ~R~tions of wa~er such as are c, Care a~ ~o me~hods and materials us~ :.~
found in ~p~ng-fed marshes_ Cost of ~n~enmqce ts low as Ash~s and cinders m~ wi~h e~h is preferable- Large
the rock f~ing prevents erosion ~d ~v~g of the dish fRls may ~ made of e~th ~d r~k, but waste of an ap-
w~ls. proved ty~ may ~ ut~d.
~uble d~ker d~i~. The ~-~ "double d~ker" Control of vegetation. Wat~ ve~tation ~d shorel~e
~ain has ~n of v~ue m ~ ~ whe~ the~ is a ve~tation ~ k~wn ~ ~'e ~ ~ for mosquiW
~w of wa~ at ~ ~ ~t ~ t~ volme of wa~r b~ing, h was c[~[y s~wn that the ~t~mg oi wa:~
1018
d~stnut, s in the Potottmc River r~ducsd the Anopheles oaler. .
quadrimaculatu$ to the point that the n~c~sity for 12. ~ m l~rinmri]y · ~ ~li~m~.
~,plane dusting was eliminated. In order to be effective 13. The optimum tampe~ture for ¢lev~opm~t of be-
the cutting must be begun sufficiently early in the year to nigh tertian malaria is 77 dagrms F., for quartan malaria
prevent re-seeding for gro~h the follo~4ng year. 72 ~ F. for malignant malaria 84; ~ F.
Another method of plant destruction which is effective 14. Tlae malaria germ will not develop in the ~tom~ch of
~lso increases the pollution of streams. This method is by tbe mosquito if the t~mperature be less than 60 dagrees F.
chemical destruction. Compounds of the tvpe of 2. 4-D 15. At the optimum temperature, the malari~ &ravine in
~l)i( hlorophenoxyacetic acid~ which are plant hormone the mosquito ~411 develop completely as follows:
phytocides have been used for effective destruction of wa- ·. Benign tertian germ {P/asmod~ rio·x) in about 11
ter plants and marginal growth by the simple method of days.
spraying. Such practices may reduce some field operation b. Quartan malaria germ (Ptasmod/a ma/ar/·el in 18 to
budgets by as much as 40%· 21 days.
' c. Malignant malaria germ (Plusmodia falciparum) in
10 to 11 days.
THE RATIONAL OF INSECTICIDING. 16. The water stage of most mosquitoes in more or less
Timing of Control Measures. Lam, it(ding and imagocid- optimum conditions is about 8 to l0 days.
lng (killing adults~ must be timed correctly because ma- 17. Malaria is usually rare above several thousand feet
iarie is essentially a seasonal disease: mosquito breeding is altitude.
o-clic with the season: some mosquitoes are more 18. The disturbanceofthesoilby man usuallyincreases
preva]en~ during' one season, others at another season, the the prevalence of malaria by creating conditions for the
hfe c.vci~: of the malaria gem; is also rh.;~hmic depending anopheles to develop·
mos:l) on the season and temperature. 19. Malaria is most prevalent where natural drainage is
poorest.
Thus. it is necessa.~.' to know the seasonal, diurnal, and
chin·tic habits of mosquitoes, and the seasonal and cli- 20. Mosquitoes are sensitive to changes wrought in
ma::c habits of the malaria parasite in order to be able to their environment.
k,.s:itute rational measures of control. Mosquitoes may hi- In carrying on a program of la,'lc(ding or adult destruc-
be,~a~e over the winter season and possibly cause ma]aria tion. it is very important that the plan be organized on a
iniec~io~ the foliow;.ng spring. In some places· as in long time basis, and that the measures adopted be exe-
Amsterdam. the germs carried by. the Anopheles degener- cured with clock like regularity. A larviciding program re-
ate dur;.ng the winter and therefore the mosquitoes must quires that the same place be treated at regular intervals
be re-infected the following spring by biting malaria car- depending on the length of time it requires for certain
tiers before they are again capable of transmitting the dis- ~ .~l~es of mosquitoes to develop into larvae from the time of
ease. In the first instance where infected mosquitoes ?,it,er- deposition of eggs on the water except where the larvicide
hate c~ er tht win:er, emphasis should be put on spraying leaves a long period residual toxicity. Since the duration of
a}! ch., hab,:ta:,,-.:~ ~u: h;,u~e-, stab]es, and such ?]a-'.',:-_~ :~ this period is variable with the season and t.;.-pes of mos-
~?,+ ar~:. ;,E,:'-r~ ~:,:,s,~c::.~,(.s k'.7 ~n order tt, d(.s:r,:',', ~.- quito, the sanitarian must kno~ enough about the life
r~a:':'. :r.:=c :~.c;...~ sq~ t: e: as p..';ss.:,ie before spri.~g. In the habits of the particular mosquito to make sound judg-
ia::~r cas~. whert th~ gerrr.;s ;r, the mosquito degenerate meat. V~'here residual toxicity larx'icides are not used.
during th,.' wmtor, emphasis should be put on the el(mina- weekly treatment of ponds, pools, etc. with larvicide
t~or, of human carriers from the area by medics! means usually suffices in temperate and subtropical areas. In
Tnes~ t-~,, exan-,ple- ,.',f hc,~ ','ar~c~- fa3tors mdica~; t.h~- tropical areas where the development of larx-ae may be
tyr, v c.f en':;:b, asis c;: rr..',.':v.r:a cc.-.:ro2 is not tc. be takt-n as quicker, the treatment of waters may be necessar.y at
abas. ,~..- bec'a=;=6 tr. thost pl~;':es where finances and fac(!:- shorter interx, a]s. The temporaD- waters formed should be
t~es are adequate al: methods of control measures are in- treated not less than 24 hours nor more than 72 hours after
~tituted. but where such facilities are limited it is impor- the rain.
tam to know where to place emphasis on control. Adult mosquito destruction by ~praying can indeed be
Some factors which may influence control measures are: ~[ective ff carried on with re4pdsrity and efficiency. The
1. In the Temperate zone, malaria i~ relatively absent, int~n-val ~t which habitations in a commtmity ~ould be
2. In the tropics, malaria is perennial, but most pre- ~pmyed dspends eslmelslly upon the r~idual toxicity of
the imu~ticides, and the residual build-up from repeated
va(eat at the beginning and end of the rainy season.
3. In the subtropics the greatest prevalence of malaria spraying. Pyrethrium spray has a very. short r~idual toxi-
city, and a fair residual build-up from repeated spraying.
i~ USually during the rainy season.
4. In contro! of malaria, it must be understood that the Therefore, habitation spraying with pyrethrium should be
~gl-,: of th~ anophe]es is rarely over I mile. daily at the beginning to allow the residual build-up, and
5. In mosquito controI it mus~ be understood that later the spraying ma.;' taper off to one or two week inter-
· orne salt marsh mosquitoes have flight ranges of many vals. With the use of synergists the duration of the res(
miles. - dual toxicity in lengthened. DDT spray has a v~j good
~. Some mosqui~es develop only one brood at a par- residual toxicity and residual build-up. The residual toxi-
titular time. and other mosquitoes' ma.;' develop several city resulting from a single spraying of walls and ceilings
br,oo~ doting e sea~ r, at the rate of 200 mg. of DDT per square foot give effective
5] .... ~.: ~: ..... ~.r,- ~.:: r~c~ eo ~,v p]sce~ used ~or ac .~ ..: ! mosquito killing for at least a sc-as,,;r,. ~he duration of effec-
~, : ' · tec. t~x'e if carried t,n within a radius of 1 mile around the
or area to he protected. This would also be effective for a
ah,..2u~ outbu'ildings, latnnes, storehouses, stables, co·.
· emp:x boxes, barrels and the like. When da~r) good deal of Aedes and Culices. but not fora(].especially
~'z:('- the, ~eck .tEe ex~t~ o; the house and may bt' .*~ :;nd not the salt marsh mosquitoes. Larx'iciding against Psoro-
or sc.;~.:. '(ir~.~, ·no w'..nd,~- ' phora is effectixe if done for a 200 yard radius around a
9. M~squitoes do not usual!v like wind. community.
10 A.,opheles ta_~ ae are suffice feeders, others are sc;..,- The secret of an.;, successful mosquito destruction ~
~t~rtsce feeds.rs gram depends on:
1! Most anopheles like fresh water. ~ome are not part(- 1. The effectiveness of the insecticide and tl~ ef~i-
M}I9
~ of the equipment. Oil application. .ncimu~ to be · suitabi~ means of kill.
2. Th~ meticulous at~ention to all details, large and im~ Is~, such as/ue~ o//mixed with 0.1% Triton X-lo0,
rig°ute. ~ppli~l a~ · rate of 2 to 3 g~l./A. F~it M. L. 0. at 2
3. The mental ~nd physical firns~ of the pemonnel. ~I./A, and ~ o~ with · 0.1% spmed~g agent
4. The ability to stick to routine except under emerges- (T-Der-MCI at 3 g~l./A gives similar r~tlts.
cy conditions, and then the ability to vaD' the procedure in
accordance with the knowledge of the habits of the species
to be controlled. ?ele ~.
The spread of malaria depends upon 3 fundamental fac- T;~, ~
tOTS. Apphcatm~ Tot·cantb Dt~ge i Remarks
1. The presence of malaria carriers.
Lb ae~ IApply by Wound equipmem
2. The presence of a sustained temperature of (50 de- ~b,te 0.05.0a lot *~ *~ ,,~,
grees F. or above long enough re allow the malaria para- {~0 q~r~ o~ ~ormu~-t~
site to develop to completion in the mosquito, ac~, a~ ~poo
3. The presence of susceptibles, cblorpyrifl~r'e 0.012~-0.06 [¢eutr~tio~ employed
Just as in most communicable diseases, the presence of ~ pa ~, ~ emule~,
EPNc 0075-0.1 {muin~lam in mr~s wzth mm.
the malaria carrier is among the most important condi- femh~onc.e,f 0.06-0.1 {imum vegetmtive cover.
tions for sustaining this disease in the community. The ~ w~,, ~,~,~u~, ~o~?
· hf~vy. Us~ ~q'allular for~-u.
human carrier of roslnria may remain a carrier for an in- ma~-th~ 0.2-0.$ ~a~ons. DO NC~ APPLY
definite period of time. The way to control carriers is by s P~ATmO~ m V~S^.~
treatment. Thus the attack on the malaria problem be- ^aE~,s. Fo~ }~-h.~h ~.,.
methozy- 0.05-0.2 n~t o~ ma m~ h~sm,
longs bo~ ~o the sanirm~n and the physician, v ~o, m.~rc~ {~ ~o
&A ~ dflcepyrdos {0.1 lb..'
Mosquito~ are the most important STOUp of arthropods ^.~. c~o~. -~
that transmit diseases to man. Control measures for mos- m v,~.t~. ~h~ Wo~-~ o~s,d e~-
quitoes, whether larviciding or adulticiding, must relate o,.~h?~ ..~..t do-o.
to the species or to a species group and cannot be consid- c urn,, t~
bred as being applicable to mosquitoes in general.
[ ~.ppiy parm green p~2let
Larv~¢~des'-(Table 1.) l] with b'~u~d eqmpment or
Table 2 shows the variation in response of 3 species of {
organochlorine resistant mosquitoes to 12 pesticides at o ti Apply to cove~ .at ......
levels of concentration which give a 95% kill of mosqui- i ~ .... ., ~,~h b ........
toes. Carba.'nc, te compounds fe.g., propexur, carbary[) £ ] ~, ~=, o~ .'~ ~ ~. g.~ .~. =.-.
generally are less tox.:c ro larvae than organochior~ne tn- .--~: ?r*- · 2tox,,~t ~ ,,,~. :
secricides. The degree of control often depends upon the ::~,~,~=,o,.,
degree of pollution and the type of vegetative cover. In [ I d.acsd,.o2w3~ A.
heavily polluted water, such as log ponds, a treatment ] {
may be necessar.' within 48 hours intervals.
'UL V~ t~chnJque with chlorpyrifos and fenthion at dos- · lA h ......... de .... to be ·pphed to crop lands, p~tum, range land ....... it,-
ages of 3 to 6 fl. oz. per acre is effective ag·mst Culex tar- ,a,,d lands c,~,su,t &gr. cultura; aut.~onttes ·~ :n acceptable compount~ a~d appaCa.
sa/is, the encephalitis vector. A bate or chlorpyrifos at b other compouno,~. ,~uch as Th·hire Le~.hane 384 propozur ~d. ronm!, ma:.- have
0.004 lb..;'A is effective ag~nst A. quadnmacuiatus with- ,,e~ ,fl. cer~,r, of .'.he caleg~m fr~,~.Llom*d, ii ~o. Iollow hill
out marked destruction of non-target orgsnisms. Aedes c For us~ b~ trained mO~lUito contzol personnel only.
species control ar~ satisfactory with 2% Abate cci·tom d ~d~ stricay ~ ~ ~p~,~caUom ~d
granules at 0.5-1.0 lb/A, 2 % Gardona at 0.15-0.25 lb./A. ~ Not to b~ ~.opl~l ~o .~t~e~ eo~t~mt~ v~lu~bl~ f~e.. cr~b~, or
or 1% cholrpyrifos granllles at 0.075-0.15 lb./A Preflood
apphcations of chlorpyrifos granules at 0.2 lb./A continue so,~. Publit lttmlth e~ieid~ C~mtar for Dis~m~ Control.
to give hills of Ab. vex·ns larvae for periodz greater than
60 days. Similar applications of 1% chlorpyrifos granules
at 0.1 lb./A give satisfactory kills of Ae. can·de°sis larvae
for at 4 weeks. Methoxychlor {5 % I granules'applied as a Table 2. [.C9~ ,e, els 'ppmi for ,'e ...... ~c,,c,d~s ag~,rmt thr~ mosqmw
preseason larvicide for Aedes control is effective at a rate .,~,,, re, is[ant to organochlonr~ compo~nd~.
of 1.0 lb./A,
Chlorpyrifos is effective against Ae. ta~niorhynchus and ^ i c.~.
A. albimenus larvae as preflood treatment at 0.5 go 2.0 i,,~ctlnde q,~a,,,~,.~t~; . ~,,~q,,f~t~ ~¥.o~:
lb. A. At 41b.. A. carbarvl is effoctive against Ae taenior- ~ate .~ oo~ [ opm
/- .,.m-bus while propoxur 12 lb., A: and .4 bate 14 lb. A~ pr()- pm~'~.xur C, .5 ] 0 5
duces 6 weeks of effectiveness. In polluted wa~er, cmo? .ar.~arv, 2 h I ~ S
pyrifos, [enthion~ andA bate have proved effective against '~'+'l'""°' ~: 01 ! c 02 :: '
Culex. Gardona suspension 12.5'%~ or methoxvchlor '-.,h,orl"~'k'r'p'r'~c~ rlg ilt~4{Y2~ [ 00 00400~
{ i .25~ ). orDDT (1.25%1. orAbate {1 ppm sand granules} C;·rdo,. ~ .~ j 0.s 0
gives satisfactory control of Ab. aegypti in urban areas. ,~-,h,o~ o ~ [ 0 ~
Anopheline larvae have b~en effectively controlled by 2 ~.,~,,:..~o, o ~ [ o 5 e:
properlytimedULVapplicationsoffenthioniO.O751b/A.i r~,,.'. ..... t~.y~ 00; I 001
~h~on methvt 0 025 [ 0 0{~
· ULV $ Ulwa. Lo=.Vohu~s ' J
2 Pubic H~mlt.~ Past,cid.s, C~, lineal; Co~.rc~. p~ 18.5o. April. 19.~J L(' ~ L~th~ concent, r~tmm
1020