of maricopa county

2801 West Durango Street Phoenix, Arizona 85009 Contact: Kristine Rabe Phone: 602-506-4708

AGENDA November 5, 2020

Flood Control District of Maricopa County

PRESENTERS:

Michael Fulton Director

Karen Scott Finance and Contracts Division

Manager

Steve Brown Senior Geotechnical Engineer

Steve Waters Flood Warning Manager

Flood Stakeholder Group

GoToMeeting

2:00 – 3:30 pm

1. Welcome and Comments (Michael Fulton)

2. Fiscal Year 2020 Budget Summary (Karen Scott)

3. Intergovernmental Agreement (IGA) Audit (Michael Fulton)

Findings/recommendations

Information requests to Mayor/City Managers of Cities/Towns

4. Fiscal Year 2020 Floodplain Management

Update (Michael Fulton)

5. Project/Program Updates (Steve Brown and Steve

Waters)

Cave Buttes Dam Auxiliary Outlet construction

Flood Warning Program Report

6. Round Table (All)

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November 5, 2020

WelcomeFlood Stakeholder Group

1

Agenda

• Welcome and Agenda Review• Fiscal Year 2020 Budget Summary• Intergovernmental Agreement (IGA) Audit• Fiscal Year 2020 Floodplain Management Update• Project/Program Updates• Round Table

2

FY 2020 Year-End Budget Update

Angie Flick

Chief Administrator

Agenda Item #24

FY 2020 Percentage of District Revenue

4

FY 2020 Percentage of District Expenses

5

Ending Fund Balance

6

Engineering Division

EAP Structures

• 5 Emergency Action Plans (EAP) Completed

• 22 annual EAP reviews

• 609 Right of way permits submittals review

• 46 Right of way permits issued

7

Floodplain Management and Services Division

• Two delineations complete

• Two with FEMA• 296 Floodplain use

permits issued

8

Planning and Project Management Division

• Middle Indian Bend Wash ADMS

• Gila Bend ADMS

• Cudia City Wash

• North Mesa ADMS Southtown- Area 2

Complete - Planning Studies

Dam Safety

• Earth Fissure Monitoring

• Dam Settlement Surveys

• Formal Inspections9

Major Maintenance

• 33 Projects completed

• Pipe repair

• Painting

• Fall prevention

• Storm damage

• Vegetation thinning

Indian Bend Wash Pipe Repair

10

Major Maintenance

ACDC Fence Painting Signal Butte FRS Safety Rail

11

Major Maintenance

Damaged fence along ACDC Fence repair along ACDC

12

Major Maintenance

Vegetation clearing along New River Vegetation clearing along Salt River

13

Completed Capital Improvement Projects

McMicken Outfall Channel

14

Completed Capital Improvement Projects

Durango Regional Conveyance Channel 27th and Olney Basin

15

Ongoing Capital Improvement Projects

White Tanks #4 Outlet

16

Cave Buttes Dam Modification

Ongoing Capital Improvement Projects

17

Cave Buttes Dam Modification

Ongoing Capital Improvement Projects

18

QUESTIONS?

19

Intergovernmental Agreement Audit

Michael Fulton

Director

21

Agenda Item #3

What was audited?Intergovernmental Agreements to design, build, operate and maintain flood control structures in partnership with cities/towns or other government entities were examined.

Recommendations/actions:• Improve documentation of project acceptance by project

partnerso Action Item: Upon project completion project partners

will be asked, by letter*, to confirm project acceptance.

Maricopa County Internal Audit of Intergovernmental Agreements

21

• Request that project partners periodically reaffirm their performance of structure operation and maintenanceo Action Item: At the beginning of each calendar year,

project partners will be asked, by letter*, to reaffirm that they are operating and maintaining structures as agreed to under the IGA.

*Letters will be addressed to the person/position who signed the IGA on behalf of the project partner. They, or their designee, will be asked to reaffirm their compliance with the IGA.

Maricopa County Internal Audit of Intergovernmental Agreements

22

• 232 known IGAs in place that include obligations to operate and maintain flood control structures

o Dating from 1966 → present

o 39 different project partners

• Letters to be sent to project partners late November/early December, 2020

Maricopa County Internal Audit of Intergovernmental Agreements

23

QUESTIONS?

24

2020 Floodplain Management Plan for Unincorporated Maricopa County

Michael Fulton

Director

Agenda Item #425

The FMP is…

an overall strategy of programs, projects and measures aimed

at reducing the adverse impacts of flood hazards within

unincorporated Maricopa County (UMC)

Why is the FMP important?

• Serves as a roadmap for District hazard mitigation activities

• As a participant in the National Flood Insurance Program’s

(NFIP) Community Rating System (CRS), this plan must be

updated every five years

• Participation in the CRS makes flood insurance discount

available to residents and businesses within UMC

26

2020 Update: Floodplain Management Plan (FMP) for Unincorporated Maricopa County

Process for updating

• Committee formed representing members from the general public, non-profit organizations, businesses and local governments

• Flood hazards assessedo Location and extent

o causes

o impacts

• Goals established

• Action plan developed to accomplish the Goals

27

Transportation and Low Water Crossing Mitigationo work with transportation agencies and the communities to address road

flooding that results in interruptions to normal operating conditions,

delays of emergency services, negatively impact the economy, or pose

safety risks.

Funding Evaluation of Process and Dedicated Resourceso work in partnership with stakeholders to evaluate its various programs,

fiscal opportunities, and funding processes to assure funds continue to be

invested back into the communities.

Education and Technical Resourceso work with stakeholders and local organizations on consistent county-wide

technical and educational materials for flood preparedness with materials

available in physical locations as well as electronically.

28

2020 Goals for the District

Managed Open Spaceo continue pursuit of nature-based solutions for flood mitigation, wherever

practical, working with stakeholders to maximize the community co-

benefits of flood control projects, including open space and recreational

opportunities.

Regional Leadershipo continue to perform duties as the regional leader in floodplain

management, provide and communicate information, guidelines, and

regulations to agencies and communities throughout Maricopa County

and to adjacent Counties.

29

2020 Goals for the District (continued)

• Continue to identify flood hazards before development occurs

• Inform the community of changes to floodplain regulations and permit requirements

• Continue to work with stakeholders to identify mutually beneficial projects

30

2020 Action Items:38 Identified for the District – General Themes

• Through partnerships with transportation departments, identify and address road related flooding hazards

• Enhance communication with communities regarding flood control project funding opportunities

• Develop educational resources for private property owners regarding maintenance of drainage infrastructure

FCAB endorsement (received September 23, 2020)

Board of Director’s adoption

District and partner implementation

Periodic progress reports to Committee

31

Next steps

QUESTIONS?

32

Cave Buttes Dam Modification ProjectAuxiliary Outlet Tunnel – Construction Update

Steve Brown, P.E.

Sr. Geotechnical Engineer, Dam Safety Branch

Agenda Item #5a33

34

Outline

• Brief Project Summary

• Construction Update

35

District Dams Vicinity Map

36

Cave Buttes Dam Impoundment - 2010

• Goal to reduce drawdown time from ~55 days to ~30 days

Why we are modifying the dam…• Existing outlet is a single 45” diameter conduit (relatively low outlet capacity)

• The dam has never experienced a full reservoir (still untested)

RISK REDUCTION

• There are no signs that would indicate a risk of imminent dam failure, but there are seepage concerns at the dam which warrant risk reduction measures

37

• Clear seepage has been observed during previous large impoundments.

Note: A future Phase 2 is planned which would install a seepage collection system to further reduce the project risk.

Cave Buttes Dam Modification Project Design Elements

• New 60-inch diameter steel-lined auxiliary tunnel outlet

Auxiliary outlet operated to stay within current 100-yr floodplain

Ancillary Features

• Intake tower with hydraulic gate

• Outlet structure

• Gate House

• Inlet/Outlet Channels

• New stream flow gauge downstream38

Cave Buttes Dam

Dike #2

Site Map

39

Project Location

Design

Tunnel972 ft.

40

Intake Structure

Outlet Structure

Construction Update

• CMAR: Coffman/SSC Joint Venture

• $14.5M Construction Contract

• NTP December 12th, 2019

• Start of Tunneling April 8th, 2020

• Tunnel Daylighting September 8th, 2020

• Completion Spring 2021

CURRENTLY ON SCHEDULE with NO COST INCREASES

41

Tunnel Machine Delivery 4/6/2020

42

Operation from above

43

Tunnel Machine Launch Day 4/8/2020

Tunnel Machine Operator Inside

44

Hard Rock Tunnel FaceInside the Tunnel

45

Tunnel Machine Daylighting 9/8/2020

46

Tunnel Machine Daylighting 9/8/2020

47

Remaining Work

• Tunnel Grouting

• Intake and Outlet Structures

• Inlet and Outlet Channels

• Gate House

• Access Roads

• Site Restoration

48

QUESTIONS?

49

Flood Warning Program Report

Steve Waters

Flood Warning Branch Manager

Agenda Item #5b50

For Today…

• Report Purpose

• Program Mission

• Program History

• Present-day Program

• Budget History and Staffing

• Comparison to Similar Programs

• Program Future

51

Report Purpose

• One of several District programs for which a detailed report was or will be requested by Management

• Provides a complete overview for incoming Management and Board Members

• Published on our internet page for viewing by the media and the public

52

Program Mission

• Maricopa County Mission:

o … to provide regional leadership… and necessary public services so that residents can enjoy… a safe community.

• The Flood Control District of Maricopa County (District) Mission:

o … to reduce the risk of flooding so that property damage and loss of life are minimized…

• The Flood Warning Program (FWP) Mission:

o To provide real-time and historic flood-related information to agencies and the public to protect lives, property and flood control structures.

53

Program History

• 1978-80 floods on major rivers and flood control structures indicated the need for real-time hydrologic information.

• County Hydrologist Les Bond (1978) “the county must consider the potential for liability for damages and the present inadequate rainfall data upon which we base our hydrology for flood control structures.”

• Automated Local Evaluation in Real Time (ALERT) technology was being developed in central California at this time.

54

Program History (cont.)

55

Present-Day Program

56

Present-Day Program (cont.)

57

Present-Day Program (cont.)

• Planning

• Detection

• Communication

• Actions

• Maintenance

• Exercises

58

Staffing

• Branch Manager

• Senior Hydrologist

• Meteorologist

• FWP Specialist

• Water Technician Supervisor

• Water Technicians (4)

59

Budget History

60

61

Comparison to Similar Programs

• Maricopa County has the largest jurisdiction in area, and a square miles to rain gage ratio of 34. Houston and Denver are 17 and 11 respectively, or approximately twice the density.

• Staff sizes for Maricopa County, Houston and Denver are very similar, but FWP maintains more than twice as many rain gages over an area five times larger.

• Costs to install a single automated rain gage are similar across agencies, with the exception of Denver’s $3,000 labor cost which is attributed to contract pricing.

• Only two of the four agencies use established Flood Response and Emergency Action Plans.

62

Flood Warning in the Future

• Electronic parts will become faster, smaller and cheaper

• Increased use of video monitoring

• Doppler RADAR used to measure surface water velocity

• Better rainfall intensity estimates from weather RADAR

• Computing and data storage in the Cloud

• ALERT stations evolve into a wireless local area network (LAN)

• 3-dimensional maps of storms and flooding

63

QUESTIONS ?

64

Round Table

• Share information of interest to the FSG.

• Comments/suggestions regarding FCD programs/practices?

• Future meeting topics?

65

Agenda Item #6

Thank you for attending!

Next meeting is January 14, 2021

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