Fiscal Year

2019-2020
A Year in Review

Thunderbird Paseo Park,
part of the Arizona Canal
Diversion Channel

ON
THE
COVER

Rainbow seen in the New River Dam
area

For 60 years, the mission of the District has
been simple: we identify flooding hazards,
inform the public about those hazards and
develop solutions to reduce those hazards.
In 1959, only three individuals were tasked
with this mission. Today the District employs
nearly 200 people with a variety of skills
and backgrounds. Still, we are united by
the same mission. This mission connects
us to those that came before us laying the
foundation and those that will follow us and
continue the legacy we leave today.
During Fiscal Year 2019 - 2020, the District
spent its resources refining the things we
do best – protecting people and property
from the impacts of flooding. 60 years of
structures placed around Maricopa County
have offered residents this protection, but
the development and urbanization of the
County has ushered in a new era at the
District. Typical large-scale projects have
given way to small-scale solutions to reduce
neighborhood flooding. Major maintenance

and rehabilitation projects were worked
on this year to ensure these flood control
giants continue to provide this protection
for the next 60 years.
Technology is not just our future but our
present. Our use of smart technology like
drones and tall-pot trees not only lead to
more efficient projects but has also attracted
national attention for our innovative approach
to government.
As we look at the past and toward the
future, I am honored to have been able
to play a small part in that work and look
forward to what the District will accomplish
in the next 60 years.

Michael Fulton, Director

22
DAMS

PROTECTING

TOWNS
AND

4.4
MILLION
PEOPLE
IN

DAMS
Tightly compacted dirt structures that
collect stormwater and slowly releases
it back into the natural waterways.
WATERSHEDS
The geographical barriers that
determine where water drains into
rivers.
CHANNELS
Man-made waterways for collecting
and safely transporting stormwater
away from people and property.

MARICOPA COUNTY

BASINS
Temporary stormwater storage areas
often used as parks and open spaces.
ALERT STATIONS
The network to detect rain, stream
flow and weather information to
predict flooding.

43
WATERSHEDS
122
MILES OF

CHANNELS
AND

370

ACRES OF
BASINS

MONITORED BY

409
ALERT

STATIONS

ABOUT THE DISTRICT

24
CITIES AND

GAGE VS. GAUGE?
The District uses a number of different kinds of gages,
but it is understandable to think that it is misspelled. Turns
out, there is a debate between scientists and spell check.
This difference comes from the work of a man named
Fredrick Newell.
In 1888, Newell was appointed to the US Geological
Survey (USGS) Irrigation Survey created to evaluate the
potential for dams and canals in the western US. At that
time, there was no practical way to collect daily streamflow
records. Newell developed water measurement methods
that are widely used by the USGS today.
Newell is reported to be the person responsible for the
use of the spelling gage instead of gauge. He reasoned
that gage was the proper Saxon spelling before the
influence of other cultures added the u. Historians have
also attributed influence to Newell for the adoption of
gage in The Standard Dictionary of the English Language,
the first dictionary produced by Funk and Wagnalls.
The District uses the spelling gage to be consistent with
the USGS and other federal agencies.

AZARDS
H
IFY

PROJECTS IN PROCESS

287
63

SQ. MILES MODELED

FLOOD USE PERMITS ISSUED

7

RIGHT OF WAY
PERMITS ISSUED

CITIES

HOMES WITH TARGETED FLOOD
PROTECTION

TS

50

3

AC

SMALL PROJECTS

IM
E
MITIGAT

P

PMENT
ELO
EV

PERM
IT D

•
•
•
•
•

Arizona Canal Diversion Channel Fence Repairs
East Maricopa Floodway Low Flow Channel
El Rio Pilot Project #2
McMicken Dam Outlet Channel
White Tanks Flood Retarding Structure No. 4
Outlet Channel
27th Avenue and Olney Storm Drain
Durango Regional Conveyance Channel
Rawhide Wash Flood Hazard Mitigation
Sun City and Sun City West Drains
Mandan Street Drainage Improvements

DAM REHABILITATIONS/IMPROVEMENTS
•
•
•
•
•

McMicken Dam
Vineyard Flood Retarding Structure
Buckeye Flood Retarding Structure No. 1
Powerline Flood Retarding Structure Channel
Cave Buttes Dam Outlet

FLOODPLAIN DELINEATION STUDIES
•
•
•
•
•

Lower Gila River Overflow
Fountain Channel
Hassayampa River
Mesa Zone D
Sunland Avenue Tributary

AREA DRAINAGE MASTER STUDIES (ADMS)
AND PLANS (ADMP)
•
•
•
•
•
•
•
•
•

Metro (Phoenix Area) . ...........75 sq miles
San Tan West ..........................31 sq miles
North Mesa ............................20 sq miles
Middle Indian Bend Wash ......34 sq miles
Cudia City Wash......................14 sq miles
Desert Mountain ....................27 sq miles
Downtown Mesa ....................20 sq miles
East Shea Road Corridor ........51 sq miles
Sun Valley .............................190 sq miles

COMMUNITY RATING SYSTEM/AFFORDABLE
FLOOD INSURANCE

RISK REDUCTION

IDEN
T

9
462

ADMS/ADMP IN PROGRESS

•
•
•
•
•

The Flood Control District of Maricopa County maintained its
Class 4 Rating. This offers unincorporated county residents
up to a 30% discount on their flood insurance.

ON THE ALERT
Every second counts when a flash flood is
heading towards people and property, as they are
quick, unpredictable natural disasters that pose
grave danger to anything in their path. District
personnel have made flash flood early detection
and warning a top priority to protect Maricopa
County from this hazard.
The District was recognized for its advancement in
flash flood early warning and detection this year.
Predicting how quickly water collects behind dams
during a flood event is critical to flood warning for
residents downstream of dams. New software was
developed to collect data and estimate dam fill time
and outflow, significantly improving early prediction
capabilities and potentially saving lives and property.
This new software interfaces with the 356 precipitation
gages throughout Maricopa and surrounding counties

and the 217 water-level gages on streams, channels
and dams that make up the District’s comprehensive
ALERT network. The gage data is then transmitted
back to the District in real time, using the data as the
input to predict dam fill time and dam outflow. The
software can self-correct the prediction results based
on real-time measurements of water level values
in the reservoir. With this tool, the Flood Warning
Branch is alerted to the flood risk up to several hours
in advance.
In addition to the dangers posed to Maricopa
County’s dams, river and wash crossings become
increasingly dangerous when flash floods strike.
This is especially true in the undeveloped and
remote outer areas of the County where it can take
hours for County crews to arrive and barricade
the roads. The District’s ALERT network stream
gages collect data that activates flashing signs

found at these types of crossing. Drivers have
the information needed to safely avoid the threat
of flooded crossings. The District’s continued
commitment to using technology to provide
maximum protection includes two sets of flashings
signs installed this year on Skunk Creek in the New
River area, one set at 19th Avenue and one set at
Honda Bow Road.
In June 2019, the Woodbury Fire destroyed
thousands of acres in eastern Maricopa County.
Burn-scarred ground does not absorb rain
effectively, and runoff creates an increased risk
for flash flooding. By July, the District had already
installed three new rain gages in the area, adding
to the lead time needed to warn drivers of
potentially dangerous road crossings. This quick
reaction delivered immediate benefits to residents
in the area before the end of the 2019 Monsoon.

EYES IN THE SKY
Proactively monitoring and maintaining the
County’s network of flood control structures is a
top priority for the District – and a serious logistical
challenge given the County’s rough terrain and
vast acreage. A drone program has been instituted
to overcome these challenges, giving staff a bird’seye view of all of District structures.
Drone photography creates significantly less
expensive aerial mapping and delivers more
accurate and actionable data faster than ever
before. Drones reach remote facilities, often
inaccessible to staff, providing that critical set
of eyes to inspect the existing conditions of a
structure. The drone program also assists the
District in monitoring active construction projects
across the geographically diverse County. Progress
can be monitored and evaluated for adherence to
design plan.
Most importantly, the District drones stand ready
to safely view levee, dam, channel and basin
performance in a flood event. Proactive and
forward-looking, the drone program is merging
the District’s mission with 21st century smart
technology solutions.

Precision is key when it comes to maintaining the
complex network of flood control structures throughout
the fourth largest county in the US. District staff
frequently conducts field visits for projects, taking
photos and noting the exact photo location, camera
orientation and date the photo was taken. This data is
collected and compiled into reports that are used by
every workgroup within the District. Compiling this data
from the field is a very time-consuming task that used to
take from several hours to several days. District software
engineers recognized the opportunity to return valuable
time back to District engineers, hydrologists, planners
and maintenance crews to do more of their work that
keeps people and property safe from flooding.

TIME SAVINGS
FY 2020 TOTALS

6.1

HOURS OF
CONSTRUCTION
MONITORING

12.9

HOURS OF
INSPECTIONS

12.8

HOURS OF
MAPPING

The District needed to automate this process and
reduce data collecting and compiling time down to
minutes or even seconds. To that end, staff created
a tool that automatically generates a photo location
map, a PDF and PowerPoint that contains the index
map and all field photos with detailed information, an
organized digital folder system that stores photos by
stops and a GIS file with live links to the photos. After a
field visit in August 2014, one engineer spent six hours
to manually process and organize these field notes
and photos. This new software was recognized by the
National Association of Counties for its ability to create
a similar report in only 14 seconds.

GOVERNMENT EFFICIENCIES

WORKING SMARTER

STEM EDUCATION PROGRAM
The District has prioritized reaching the County’s
youngest residents to help them understand
how urbanization can affect the way the water
flows in the desert. The Science, Technology,
Engineering and Math (STEM) program has
lessons specifically designed for County school
children. It is important to reach youth because
they are receptive to new information and likely to
carry flood safety messages home to their parents
and other family members.
STEM programming also serves as an opportunity
to show how the professionals at the District study,
design, engineer, construct, monitor and maintain
the complex network of flood control structures
throughout Maricopa County. These lessons are

intended to supplement current curriculum and
can be added to instruction about the earth’s water
and weather. Developed by a former educator,
lessons have been updated this year to remain in
alignment with Arizona Science Standards.
Curriculum is available for third through fifth
grade, with a sixth through eighth grade unit
under development. In these lessons, students
participate in research projects, read background
information about monsoons and look at real
rain gage data. Hands-on lessons assist in
introducing meteorology, emergency planning
and engineering concepts. At the end of the unit,
students create emergency preparedness plans,
work in teams to solve flooding problems and

create public service announcements to warn the
public of the dangers of flooding.
Each grade level unit includes lesson plans,
PowerPoint slides, vocabulary cards and links to
websites, videos and interactive tools. Schools can
check out free resource kits with materials necessary
for the hands-on components of the lessons.
District staff from all divisions and disciplines have
attended STEM nights around the County, and new
events are scheduled throughout the school year. A
flood simulation model that demonstrates runoff in
both a natural and urban environment is the main event.
Staff is on hand to describe how designing, building
and maintaining structures reduces flooding risk.

TALL-POT
NURSERY
District structures add to the flood protection for
County residents; however, these construction
projects can have an impact on adjacent
communities and the sensitive desert landscape.
Projects continue to include a focus on limited
disturbance, effective landscape restoration
strategies and water conservation to minimize
adverse environmental impacts. The climate in
Maricopa County is arid desert, making it critical
to choose appropriate vegetation suitable to
survive the desert’s harsh conditions.
The District adopted a growing method known
as tall-pot planting in 2002. The District grows
its own trees in an innovative nursery because
commercially available trees are not suited for
flood control projects. This growing method
develops trees with deep root systems that mimic
the natural growth habit of many native Sonoran
Desert trees, allowing them to survive without
supplemental irrigation after establishment. Tallpot trees do not require supplemental water,
allowing the District to reduce the use of potable
water irrigation systems on many projects. This
reduces operation and maintenance efforts as
well as reliance on potable water for outdoor
landscaping, all while allowing the District to

mitigate construction impacts in a cost effective
way. Tall-pots mimic the natural growing process
increasing the survivability. Most desert species
have long tap roots that reach to find moisture.
The length of these roots are several times the
height of the above ground stems.
When it is time to install, a hole is drilled and
the tall-pot tree container (a PVC pipe) is placed
into the hole. The container is removed, leaving
the plant in the pit. This allows the tall-pot
container to be reused keeping operation costs
low. Dirt is filled in around the roots, and the
tree is watered thoroughly. Rain and stormwater
runoff will continue to provide water for the tree
throughout its lifetime.
To date, more than 12,000 tall-pot trees have
been planted and an additional 4,000+ trees
are planned for several upcoming projects.
The nursery grows several tree species and
has the capacity to produce up to 8,500
trees concurrently, at a unit cost much lower
than a traditional landscape nursery tree and
irrigation system.

The District has a long history of using desert
landscaping and effective landscape restoration
techniques in flood control projects. The first
aesthetics policy was adopted in 1979 and has
evolved over time. Residents have come to expect
the District to plan, design and construct flood control
facilities that preserve natural desert open space,
enhance the local community image and provide
opportunities for multiple uses including both
passive and active recreation (like desert greenbelts
and urban parks). The focus from that initial policy
has shifted from merely creating more aesthetically
pleasing structures to using trees, shrubs and natural
vegetation to aide in flood control. Using the original,
undisturbed characteristics of the desert allows the
District to mimic the flood control measures found
in nature.
Green infrastructure, a component of Landscape
Architecture, allows the District to incorporate more
cost effective, longer lasting and easier to maintain
alternatives to the concrete channels that dominated
early flood control measures. District design
features include water harvesting basins that accept
stormwater runoff for use as a native revegetation
water source. This nature-based approach treats
stormwater like the valuable resource it is and nearly
eliminates the need for expensive, ongoing irrigation.

WATER CONSERVATION

LANDSCAPE
ARCHITECTURE
AND GREEN
INFRASTRUCTURE

27TH AVENUE AND OLNEY
Monsoon 2014 brought significant flooding to
Maricopa County, and cities and towns looked
to the Flood Control District to help those
neighborhoods that were flooded. The flooding
was particularly heavy, even disastrous, for those
in Laveen. Homes in the Southern Hills and Citrus
Mountain Neighborhoods found themselves in
deep waters when streets quickly turned to rushing
rivers. Several neighbors had to rebuild multiple
times over the next few years.
In response, District planners and engineers focused
efforts on the critically affected area, completing an
updated area drainage study. The update evaluated
flooding hazards and developed alternatives

that could help reduce flooding for Laveen area
residents. One of these proposed alternatives was
the 27th Avenue and Olney Avenue project.
This large project consists of several flood control
components. A combination of basins and storm
drains, the completed project will reduce the
flooding risk by capturing and safely conveying
the stormwater away from roads and homes to
a final regional retention basin. The regional
basin was built in 2016 near 27th Avenue and
South Mountain Avenue. The basin has collected
monsoon rains, providing some relief for neighbors
in the area. The District partnered with the City
of Phoenix to build three more basins near 23rd

Avenue and Olney Avenue. District engineers
determined these interim measures, including
the basins that came into service this year, would
provide additional relief.
The District’s work is not complete - a storm drain
along 27th Avenue is being designed to transport
the water from the three new basins to the large
basin at 27th Avenue and South Mountain Avenue.
The design should be complete in the summer
of 2020. The total project is anticipated to be
complete and in place in time for Monsoon 2021.
This small-scale solution is a prime example of the
District advancing its mission while adapting to the
changes brought on by urban development.

RAWHIDE WASH
FLOOD HAZARD
MITIGATION
PROJECT

The project was a proposed alternative of the Pinnacle
Peak West Area Drainage Master Study. Engineers
are currently focused on designing a floodwall and
levee system to contain the 100-year flood. Existing
floodwalls have been evaluated. Improvements will
need to be made to those walls, and new walls must
be constructed to provide continued protection.
Once design is complete, the plans will be submitted
to FEMA for their review. This will be the start of
the process towards remapping the floodplain,
reducing the amount of buildings in the high hazard
area. Construction of the project is anticipated to
start in 2021.
More than 1,000 Phoenix and Scottsdale homes,
businesses and other structures are within this 100year floodplain and are at potential risk – the District
and its regional partners are working together to
provide additional flood protection to these residents
and property owners.

PROJECTS

Rawhide Wash is the third largest wash in Scottsdale.
It starts north of the McDowell Mountains and runs
through Scottsdale southwesterly into Phoenix
towards the Central Arizona Project Canal. During a
100-year flood, the high flood flows and rapid water
velocities would create a serious flood hazard. Flood
flows often create new channels and cause flooding in
areas that are not next to the existing wash. This area
is identified by FEMA as a special flood hazard area.

EL RIO PILOT PROJECT #2
Salt cedar, introduced in the 1800s for erosion
control, grows significantly denser than native
riparian plant species. This dense growth can
increase the risk for flooding along rivers like the
Gila River in western Maricopa County. In the
Southwest, native ecosystems provide high-quality
wildlife habitat as well groundwater recharge and
improved water quality. While revegetating areas
dominated by salt cedar can take 20 to 25 years
to reach its maximum environmental benefits, the
District considers this an excellent opportunity to
continue its investment in the protection of life and
property while respecting the natural environment.

pilot project, salt cedar will be removed and
native, desert-appropriate vegetation will be
planted in its place.

District staff have started work to remove 15 acres
of salt cedar from the Gila River west of State
Route 85 as part of the El Rio Pilot Project #2.
Duplicating the successful activities of the first

The revegetation area has been divided into three
areas. 500 cottonwood and willow poles were
planted in the first zone where the groundwater
is the shallowest. This section proved to be

El Rio Pilot Project #1, partially funded by a Gila
River Indian Community gaming grant, removed 27
acres of salt cedar trees and revegetated with native
species using pole-planting and tall pots. Tree
removal was completed in three weeks, ahead of
schedule due to the innovative use of a masticator
attachment. Tree mulch was used on-site to save
hauling and landfill costs and was spread over the
site to retain moisture for future plants.

challenging to tree survival, so the District planted
nearly 300 tall-pot trees in the second phase of
the project. The deep-planting technique requires
no additional irrigation and has high survival rates.
Nearly two years later, 60 percent of the tall pot
trees are alive in the project area. More importantly,
significant native vegetation has begun growing
back on its own.
The project team is cautiously optimistic about
the results thus far – no irrigation was brought into
the site allowing for the natural river and rainfall
to feed the new vegetation. However, a drop in
groundwater levels and low rainfall caused the
team to closely monitor the survivability of the
new vegetation. Maintenance of the area is also
key. To achieve the desired density, 1,600 new
plants will be planted over the next few years.

The District is currently conducting an Area
Drainage Master Study (ADMS) in the Desert
Mountain area. The Desert Mountain area
is a small, 15 square mile area that includes
residential homes, commercial areas and
undeveloped land.
In an area drainage master study, the project
team identifies the flood hazards in a specific

area based on the conditions that exist. Data is
collected from engineering modeling, physical
surveys and meetings with property owners
and others.
The results of the Desert Mountain Study will
be used to determine if additional actions are
needed to help protect property owners and
development from flooding hazards. Results

can also be used to guide future development
as well as help plan drainage infrastructure.
The project team is in process of mapping the
100-year floodplains along the major washes. This
will make flood insurance more affordable for the
homeowners that wish to buy it. Concept solutions
are also being developed by the team to provide
options for residents to reduce their flood risk.

PROJECTS

DESERT MOUNTAIN ADMS

DURANGO REGIONAL CONVEYANCE CHANNEL
The construction of the Durango Regional
Conveyance Channel (DRCC) Phase 2 is complete.
The channel was originally proposed as a part of a
regional drainage plan in 2001. At that time, the land
was mostly agricultural, but 13 housing developments
have since been planned for the area along the
project. The District resolved to get out in front of the
development to provide flood control for this growing
area of the County.

regional projects, the DRCC was broken down into
three separate phases.

Twenty years later, more than 7,000 homes are found
in this area.

The first portion of this multi-phased project was
completed in 2010. The District then partnered with
the City of Phoenix to build a channel, basin and
storm drain. This laid the foundation for the entire
project. Two years later, the District and City of
Phoenix partnered again to start design on phase two.
Phase two was designed to add three basins and four
miles of channel continuing on from phase one at 75th
Avenue and traveling out to 107th Avenue.

The DRCC was, in concept, a combination of a
channel, box culverts at the road crossings and basins.
Designed to move a 100-year flow, it would ultimately
empty into the Agua Fria River. Like many complex,

Construction of the three basins in the next portion
started in May 2018. Two of the basins are located at
87th and 89th Avenues where rainfall runoff will gather
from the surrounding homes. A final basin caps the end

of the conveyance at 107th Avenue. Flows from the
channel will gather in this basin until phase three can
be constructed. All three basins can be transformed at
a future date into recreational spaces, adding value to
the neighborhoods surrounding them.
These initial improvements provided relief to more
than 2,000 homes and even more developable lots.
Now with the addition of future phases, 4,500 more
homes, three elementary schools, several areas of
agricultural land and thousands of developable lots
benefit from increased flood protection.
In the future, phase three will continue the channel
down to the Agua Fria River. Committed to continue
its work in this area, this part of the project is currently
in the planning stage at the District.

The Arizona Canal Diversion Channel
(ACDC) was originally completed in
1994. The 20-mile channel winds through
portions of Phoenix, Glendale and Peoria.
Where the channel transitions from an
earthen channel to a concrete one, a fence
was installed to provide protection to the

residents surrounding the channel as well
as District staff.
During regular inspections, Operations and
Maintenance staff identified that several
sections of the fence along the channel were
deteriorating. This posed a significant safety
risk to the community and the integrity of

the structure. Maintenance crews made
temporary improvements to these sections
as engineers designed a replacement fence.
The project is scheduled in three phases.
During the replacement and repair of the
fence, the multi-use path has remained
open for use.

PROJECTS

ACDC FENCE REPAIRS

maricopa.gov/floodcontrol
For real-time information, follow us on Twitter

@FCDFloodInfo @FCDespanol

Construction of 115th and Union Hills Project