June 25, 2012 Minutes
CITY OF DENTON CITY COUNCIL MINUTES
June 25, 2012
After determining that a quorum was present, the City Council convened in a Special Called
Meeting on Monday, June 25, 2012 at 3:30 p.m. in the Council Work Session Room at City Hall.
PRESENT: Council Member King, Council Member Watts, Council Member Gregory,
Council Member Engelbrecht, Mayor Burroughs, Council Member Roden
ABSENT: Mayor Pro Tem Kamp
1. Receive a report from staff and hold a discussion concerning Risk Level 5 of the
Mosquito Surveillance and Response Plan of the City of Denton.
City Manager Campbell stated that this was an issue which was important to the community
concerning the Risk Level 5 of the Mosquito Surveillance and Response Plan. It required
Council approval and staff would be presenting an update on the situation.
Ken Banks, Director of Environmental Services and Sustainability, presented the status of the
mosquito issue. The virus was transmitted to humans by mosquitoes that became infected after
biting infected birds.
The City’s monitoring approach included an extensive network of traps using an average of 16
traps per week. Trapping was conducted approximately weekly from the end of April through
the first week in October. There was an approximate lag time of 7-10 days to get the results
from the State on the trapped mosquitoes. He reviewed the testing locations for the West Nile
positive mosquito traps. The trapping showed that in multiple weeks there was an increase in the
st
number of positive cases. On June 21 the City received notification from the Denton County
Health Department of two human cases of West Nile virus in Denton. The locations were in
close proximity to each other which resulted in placing Denton at Risk Level 5. The condition
for a Risk Level 5 public health alert was human outbreak confirmed and the trigger was
multiple human cases within a short time frame or clustered human cases.
The various types of mosquito control included (1) source reduction (controlled the eggs) which
was considered the most effective (2) larvicides that eliminate juvenile mosquitoes (controlled
larva and pupa) was considered effective and (3) adulticides (controlled the adults) through
fogging or spraying of chemical pesticides and was considered the least effective.
It was important to understand the biology of the mosquitoes. The eggs may be laid singly or in
clusters and hatched in 2 to 3 days. The eggs hatched into larva that only live in water and
mature in 4 to 10 days. The larva transform into the pupal stage. The city of Denton
concentrated on using a larvacide that was highly specific to mosquitoes. It did not affect fish,
frogs or other predatory insects that may feed on mosquito larvae. However, it had to be applied
properly or it was not effective. Pupae spend most of their time at the surface of water and did
not eat. This stage may last from 1 to 10 days and was controlled mainly through chemical or
surface based measures. Adult males feed on nectar and plant juices while females must have a
blood meal as source of protein before they can produce eggs. Adult female mosquitoes
typically live for about a week to a month.
City of Denton City Council Minutes
June 25, 2012
Page 2
Flight distances were important in order to find the source of mosquito problems and choose the
appropriate management strategies. Mosquito flight varied from 300 yards up to 40+ miles.
Control for adult mosquitoes was accomplished through a pesticide application. The City had a
state-of-the-art ultra-low volume fogger for this use. Denton already had a personal services
agreement in place with a contractor to apply the pesticides if needed. The application of the
pesticides would only be considered at Risk Level 5 and the policy indicated that use of the
pesticides would be a council decision.
Mayor Burroughs asked about the effects on people and animals with fogging.
Banks stated that the material used was called Duet which was on the lower end of toxicity.
These were designed to kill organisms and might impact non-targeted organisms. The toxicity to
larger animals and wildlife was relatively small. The product incorporated agitation which
encouraged the mosquitoes to fly and provided better chances of contact with the pesticide.
Council Member Roden questioned what type of company dispensed the pesticides.
Banks stated that this group was a pesticide application company.
Council Member Roden questioned if there were studies of from other cities that had some sort
of tracking data regarding these measures and results.
Banks stated it was very difficult to trace back where someone contacted the virus. The ability to
determine whether it was influenced by the application of pesticides was limited.
Council Member Roden asked if there were projections on what to expect in terms of a virus
outbreak.
Banks stated that right now it looked like a bad year based on what someone with that
knowledge would say. This was the fastest he had seen a group of traps go from one to many
being positive and the earliest seen cases in humans.
Council discussed fogging in terms of what kind of coverage would be received, what happened
when people had contact with the pesticide and the symptoms of the virus.
Banks stated that the toxicity was very low to humans but there always was the concern with
long term effects.
Council Member Gregory suggested fliers on doors to encourage people to look for standing
water that needed to be dumped out to reduce mosquito population.
Council Member Roden questioned what would happen if a neighborhood did not want the
spraying.
Banks stated that it would not be possible to assess that situation and questioned how a
consensus of the neighborhood would be achieved.
City of Denton City Council Minutes
June 25, 2012
Page 3
Council Member King suggested concentrating on the Fairgrounds and Good Samaritan to help
with the removal of standing water.
Council Member Engelbrecht felt that little pools of standing water made large problems and
spraying was not going to solve that problem. He was in favor of an aggressive way to clean out
those locations that might breed the mosquitoes.
Kiersten Dieterle stated that a comprehensive communication campaign with residents was
already in place.
Council Member Engelbrecht felt fogging would take care of front yards but not much in back
yards. He questioned if targeting an area and then looking at traps to see if the efforts were
working was possible.
Banks stated that there would be too many variables to do that.
Council Member Engelbrecht felt that there should be a system to tell people how to take care of
themselves and how to take care of standing water and suggested contacting neighborhood
associations.
Dieterle indicated that Public Communications already had that information for residents.
Mayor Burroughs suggested a door hanger indicating a Level 5 alert. The information could
include a phone number to call to provide additional information and indicate that there were two
cases of the virus in the neighborhood. If the area residents wanted to be proactive to protect that
area, they needed to look for standing water, etc.
Council Member Gregory suggested to also offer that if an individual were unable to inspect a
yard, to call and a volunteer or staff person would go out and do it. He stated that the
information staff already had on the website was excellent and very useful.He felt every method
available such as call, emails, utility bills, door hangers, etc. must be used.
Council Member Watts questioned if the purpose of this meeting was to determine whether or
not to spray for the mosquitoes.
Banks replied correct.
City Manager Campbell stated that at this meeting there was a specific set of circumstances but if
next week the same circumstances arose in another area with the same or other cases, would the
Council authorize the spraying as in the plan and move to that other area.
Council Member Gregory felt the plan was well thought out and was not opposed to the spraying
but not do just the spaying.
Council Member King stated that he had no problem with spraying.
City of Denton City Council Minutes
June 25, 2012
Page 4
Council Member Engelbrecht stated that the alert would remain at Level 5 but the spraying
would only happen at certain triggers.
Banks replied correct.
Council Member Roden stated that he was not convinced that spraying would be effective. He
questioned how to ensure that everyone got the message.
Dieterle stated that a variety of media would be used such as the different social medias and
going door to door with hangers.
Mayor Burroughs stated that there was a need to be as aggressive as possible but that spraying
would be another element to save lives and protect residents.
Council Member Watts stated that he was comfortable with spraying and leaving to the expert
staff on the number and locations of spraying. Informal staff reports could keep Council up to
date on the process.
Mayor Burroughs felt it would be best to be conservative with the utilization of spraying and to
set it apart from the other mechanisms; limit the use of the pesticide.
Council Member Roden questioned how the boundary to spray would be determined.
Banks stated that it would be a judgment call on how to best to determine the boundaries.
Council Member King stated that statistical sampling could not be done on whether or not to
spray. That was what the Council was elected to do.
Council Member Watts suggested amending the resolution to include the provision on spraying
when there were two human cases or three positive hits on one trap.
Council Member Roden suggested adding language to the resolution regarding the notification
process.
City Manager Campbell stated that the policy could always be amended as needed.
Council Member Engelbrecht stated that he would like to have a definite pattern of reports to
state where the traps were located, what was the outcome of the traps and the number of human
cases.
Council Member Gregory suggested informal staff reports on the sites and the variety of media
used for getting the information to residents.
Resolution No. R2012-019
2. Consider approval of a resolution authorizing control measures to be taken by the City of
Denton concerning Risk Level 5 of the Mosquito Surveillance and Response Plan of the
City of Denton; and declaring an effective date.
City of Denton City Council Minutes
June 25, 2012
Page 5
City Attorney Burgess read the revised wording for the resolution which indicated that the
ground based application of mosquito adulticides, as described in Risk Level 5 of the Mosquito
Surveillance and Response Plan, to include also application in “hot spots” when three or more
consecutive positive tests result from a single trap, is hereby authorized so long as the city of
Denton shall be in Risk Level 5, for the mosquito season of 2012. The City Manager shall insure
maximum dissemination of information to residents where application of mosquito adulticides
shall occur, to include actual notice to residents to the maximum extent possible.
Council Member King motioned, Council Member Watts seconded to approve the resolution as
amended. On roll call vote: Council Member King, Council Member Gregory, Council Member
Engelbrecht, and Mayor Burroughs – “aye”. Council Member Roden, “nay”. Motion carried
with a 5-1 vote.
____________________________________
MARK A BURROUGHS
MAYOR
CITY OF DENTON, TEXAS
____________________________________
JENNIFER WALTERS
CITY SECRETARY
CITY OF DENTON, TEXAS