Water control proposal for Cedar Rapids area

8/14/2019 Water control proposal for Cedar Rapids area

http://slidepdf.com/reader/full/water-control-proposal-for-cedar-rapids-area 1/85

Cedar River Flood & Water Quality Control Report &Proposal

Constructed Wetlands Coupled with“Minuteman” Retention Basin

Network for Flood Control & WaterQuality on the Cedar River

(CW / MRBN)

A statement of a problem…Cedar Rapids, Iowa (June 2008)



Friday, June 13 2008 A flood of epic scale and destruction



Other contributors to these investigative efforts that

culminated in this draft of a report and concept proposal

Initiated ad-hoc

volunteer committee

with similar ideas that

initiated this

investigative effort:

Legislative Coaching and

suggestions:

Clark RiekeJoe Aossey

Mike Richards

Robin Cash

Don Palmer

Iowa State

University

Agricultural Engineering

Staff:

Field Tile Behavior:

Rick Cruse

Matt Helmers

Rebuild Iowa

Subcommittee Chair on

Watershed issues:

Bill Bywater

Iowa Department of

Natural Resources

Coaching, sounding

board, hurdle issues…

Rich Leopold, DNR Director

DNR Watershed

Improvement Section:

Jeff Berckes, Coordinator

Adam Kiel,Watershed Analyst

Report & PowerPoint

Presentation

Senator Rob Hogg

Iowa Department of

Agriculture

Coaching, sounding

board, idea contributor,

resource coordinator

Chuck GippDirector Soil & Water

Division

Don Palmer

Tim Palmer

University of Iowa

Hydrology Department

Coaching, sounding

board & Idea

contributor:

Dr. Larry WeberDepartment Chair

Dr. Witold KrajewskiHydrology Coordinator

Other

Concrete culvert

manufacturer in Iowa

Water control hardware

vendors



Cedar River Flood & Water Quality Control Report &Proposal

Constructed Wetlands Coupled with“Minuteman” Retention Basin

Network for Flood Control & Water

Quality on the Cedar River(CW / MRBN)CW / MRBN is an “active, real-time” flood and water quality controlsystem using upstream “minuteman” retention basins and wetlands in a

network system that is integrated throughout the total Cedar River Watershed to maintain the flow and contaminants in the Cedar River

within acceptable levels along its route.

February 1, 2009 / Revision (B)

Prepared by the CW / MRBN Team Members with Legislative Guidance from

State Senator Rob Hogg & Restore Iowa Sub-Committee Chair, Bill Bywater

(First draft report pulled together for the team by member Don Palmer, 319-360-3803.

This report is still under team review for updates and improvements.)



Proposal Contents

1. Introduction to the CW / MRBN Flood & Water QualityControl System –

Learn how it works by having the systems address the

challenge of the year 2008, 500-year flood in Cedar Rapidsand not have the Cedar River leave its banks and maintainrequired water quality along its route through eastern Iowa!Learn step by step in this proposal…

2. Step 1 - Definition of how, where and the number of “minuteman” retention basins within the proposed system.

6. Step 2 - Description of the method of developing these basinsby taking advantage of the natural topography and theexisting drainage barriers.

4. Step 3 – Explanation of how this system integrates newtechnology developments within the science & engineering of

Hydrology, Laser assisted area topography mapping,expanded computer software and computational capabilitiesthat can network sub areas of watershed into a flood controlsystem.

5. Step 4 – Identification of where similar flood-prone watershedareas such as the one in Southwestern Germany and Hungary

are already implemented and using these similar principles.–



Proposal Contents - Continued

7. “Wetlands” incorporation into this Flood Control Systemand the restoration of current lands that the owners want

help in returning to their natural condition as wetland.8. Reimbursements to the land owners for the development

of these minutemen basins on their property. How can thisbe done?(Yearly benefits and additional benefits should anotherflood occur)

9. Required Flow Control Hardware items and suppliers thatare already providing these items to an internationalmarket. New remote control features that needdevelopment from established component elements.

10. Definition of the required study phase that uses theavailable technology to outline the guidelines for thedesign and implementation of this system and itsconfidence factor for handling 500-year flood levels andgreater.

11. Cost estimations of the required quick look feasibility

confirmation study, but also the projected costs and timephase of the proposed construction and implementation.



Appendix 1 Glossary of terms used within this proposal

(This section can be skipped and referred to as necessary by the readers andtheir familiarity with the terms in the field of hydrology)

“Minutemen” Retention Basins

Temporary retention basins that can be “called on” at a moment’s notice

to be changed from crop land or grazing use to a flood retention basin.

“Wetlands”

Existing wetlands and those areas that owners want to be returned towetlands are also integrated into the network of retention basins and willbe managed as wetlands as well as occasional “Minutemen” retentionbasins.

“Integrated Flood Control System”

The integration of new hydrological status sensors throughout the totalwatershed to permit real time determination of the watershed status andthe flood control measures that are available to maintain flow in the Cedar

River at its capacity level.

Proposal Contents - Glossary



“NEXRAD”Is a Doppler weather radar system with a network of stations

covering eastern Iowa that is currently deployed and functioningthat is completely “mapping” the total Cedar River watershed andcan provide data streams regarding precipitation intensity with

respect to time and cumulative amounts for specifically, definedsub-regions within the watershed. The data is there for us to useas data inputs into a new technology hydrological model that nowhas the computer technology necessary to integrate informationacross a watershed the size of our Cedar River and provide a focusof action for this network system.

(Just ten years ago, this technology wasn’t available to be used!)

“Hydrograph”

A graph showing for a given point on a river or stream the flowvolume, state (depth), velocity or other property of water with

respect to time.

Proposal Contents – Glossary / continued



“LiDAR” (Light Detection and Ranging)LiDAR or Laser scanning is a relatively new land surveyingtechnique which is based on high precision laser scanners, theGlobal Positioning System (GPS) and Inertial Measurement Units(IMUs). Combined, they allow the positioning and orientation of thefootprint of a laser beam as it hits an object, to a high degree of accuracy.

Scanning Technology within LiDAR. The laser scannerproduces an optical pulse that is transmitted, reflected off anobject, and returned to the scanner’s receiver. With the pulsetraveling at the speed of light, the travel time of the pulse can beconverted into range measurement. Combining the laser range,laser scan angle, and the laser position and orientation from Terra

control, accurate 3D target coordinates can be calculated for eachpulse. This is a robust and reliable technique that can be used inmost weather conditions.

Airborne LiDAR. The airborne mapping technique uses a laserscanner to measure the distance between the laser sensor andthe ground resulting in a surface “map.” This technique is an ideal

application for performing quick and accurate topographicalmapping of Iowa watersheds!




LiDAR Mapping in progress in Iowa.

Currently, the state of Iowa has previously released contracts for lasertopographical mapping within the state. Approximately $4.3 M have beendirected to this mapping effort. However, progress to date has beenaccomplished in Western Iowa. Presently, no laser mapping effort has beendirected for the Cedar River Watershed to date.

River Stream Gauges (New Technology)

Radar technology has been applied to stream flow measurement. Surfacevelocity can be measured with devices similar to those used on thenation’s highways by the Highway Patrol to enforce speed limits. The basephysics behind the system is the same as the frequency of a radar signalchanges as it is successively reflected by a moving object. The instrumentsconvert the changes in frequency to a velocity. Such a device was used tomeasure the surface velocity of the Skagit River in Washington State.Stream discharge measurement technology. This new technology has an

application for ground-penetrating radar. The antenna for this type of radarcan be move back and forth across a river suspended from a cableway. The instrument producers a profile of the streambed and the water depth. This new technology allows measurement during major floods whenbedload and debris transport is high and can obtain repeatedmeasurements of channel geometry when the bed is unstable. Thistechnology provides a more accurate measurement of stream discharge ascompared to the use of stream surface velocities time the “old eight-tenthsrule-of-thumb to get an estimate of the average stream velocity.




“Hydrological Model of the Cedar RiverWatershed”

A hydrological transport model is a mathematical model used tosimulate river or stream flow and calculate water level and qualityparameters. The most common parameter is surface runoff,

allowing variation in land use type, topography, soil type,vegetative cover, precipitation and land management practice.Water quality parameters involve the pollutants addressed, thecomplexity of polluted sources, whether the model is steady stateor dynamic, and the time period modeled.

“Acre-Feet of Water” This term is a more useful expression for the volume of water thatis being conceived in one’s thinking or in discussions with others.An acre-foot of water is the surface area of one acre with a waterheight of one foot level across the total acre of area. However, if you prefer English units of measure, then one acre-foot of water is

the same as 43, 560 ft3 of water or 325,852 gallons of water!Also, you can easily convert 100 acre-feet of water to 50 acres at






1. Introduction to the CW / MRBN Flood ControlSystem

How does this proposed flood control concept work?

• This CW / MRBN flood control concept will be described by

showing how it could have prevented the flood impact on CedarRapids by the 2008 flood levels experienced.

• Use the 2008 Hydrograph of the Cedar River at a reference pointwithin Cedar Rapids that shows the Cedar River flow volume withrespect to time.

(Rough approximation shown below to complete thisdemonstration.



1. Introduction (continued)

How is it proposed to store 1,080,000 acre-feet of water in these“minutemen” retention basins upstream in the Cedar Riverwatershed using this proposed CW / MRBN system?

Steps in learning how this flood control system is constructedand how it becomes an interactive network system:

Step 1Definition of the how, where and the number of Minutemanretention basins that are required for enduring a 500-year floodor great in the Cedar Rapids greater community.

Step 2Description of the method of developing these retention basinsby taking advantage of the natural, existing area topographyand drainage barriers to produce numerous low cost basinsthroughout the watershed.

Step 3Explanation of how this system integrates new technologydevelopments within the science of engineering of hydrology,laser assisted topography mapping, expanded computersoftware and computational capabilities that can integrate thesenumerous sub areas of the watershed into a network flood

control system



1. Introduction (continued)

Step 4Learn from the flood-prone watersheds such as the one inSouthwestern Germany (Baden-Württenberg) and the Tisza Riverwatershed in Hungary that have already integrated a number of these new hydrological tools and control systems to tame floodingrivers because of their country’s commercial investments already

located in these flood plain zones and the needed growthexpansions in those flood plains for the community welfare.Changing weather patterns demonstrating great amounts of seasonal precipitation that added to the river runoff wasintegrated into these new river control paradigms.

(It has been done! Why not for Cedar Rapids?)

Step 5

Configure a system for the Cedar Rapids Watershed todemonstrate this system approach.



2. Step 1

Define how, where and how many “Minutemen”

retention basins are required…

• The Cedar Rapids reference point hydrograph for the 2008 riverflow volume indicates that 1,080,000 acre-feet of water needsto be retained and released as appropriate for the flow capacity

of the river.

• Geologists and Hydrologist knows that approximately 20% of the flow in the Cedar River comes from subsurface water flowemitted from the natural water table and natural springs. Mostof this subsurface flow is accelerated by field tile networks that

occur widely throughout the upper Cedar watershed.

• Placing remote controlled water flow gates at the outlet of thesefield tile networks can result in the upriver basins to begin toretain water flow from the “subsurface up” as well as on top of the basin!



2. Step 1 (continued)

• Therefore: (20%)(1,080,000 acre feet of water) = 216,000 acre–feet of water that will be retained within the subsurface withthe closed gates of the field tile networks. This leaves 864,000acre-feet of water that needs top surface minutemen retentionbasins.

• Definition of some characteristics of the Cedar River watershed.See figure 2.1 for a map of the watershed and figure 2.2 for amap of the Cedar River and tributaries, along with numeroussmaller streams and creeks that drain the total watershed.



Figure 2-1 The Cedar River Watershed Characteristics Reviewed

• Approximately 6510

square miles in the

watershed aboveCedar Rapids.

• There are 4,166,400

acres of land in the

watershed above

Cedar Rapids• The bulk of the

watershed above

Cedar Rapids has a

gentle slope of 2%

• Water quality issuesare of major concern in

many streams that

carry excess nitrates

and other certain

bacteria.






Natural existing watershed characteristics determines the size,number and locations of “minuteman” retention basins to bedeveloped to meet FY 2008 Flooding levels in the future.

• Earlier it was calculated that the 2008, 500-year flood level inCedar Rapids would require the retention of 864,000 acre-feetof water in the upstream “minuteman” retention basins.

• The natural or “minuteman” retention basins will be sized to fit

the opportunities that the local topography presents.• The required 864,000 acre-feet of water can also be made

equivalent to other area amounts at other vertical storageheights and number of acres as demonstrated in the examplebelow:

The 864,000 acre-feet represents one foot of vertical storage height across of

the area of 864,000 acres. By shaping natural drainage basins within a localarea into retention basins that will have an average vertical height of 3 feet of topsurface water retention, the following options can be calculated to be equivalentto the one foot amount over the 864,000 acres:

Quantity 3800 basins with 3 feet of height over 60 acres of area

and Quantity 2000 basins with 3 feet of height over 30 acres of area.

- And so forth…to develop natural basins of vertical heights to equate thevolume.

This combination of basin areas at 3 feet of water sur e will re uire the use of




The task of locating over five thousand “minuteman” retentionbasins within the Cedar River Watershed is a large and critical

task. The risk of not being able to complete this task must beaddressed early because the flood mitigation approach definedin this proposal does not have alternate options should therequired number/size of these basins not be found within thenatural topography of this watershed. Only a small amount of man-made levee-feet can be built to enclose the required

amount of upstream water storage volume and meet the costgoals of this proposal.

To assure the task of locating this large number of retentionbasins, time was spent within the Iowa DNR with the watershedsupport personnel and evaluating the current data bases andwatershed software tools that could address the watershedlocation challenge and to be able to size the local regionwatershed draining through some restriction such as a countyroad culvert.

The Iowa DNR has excellent software tools and reasonableCedar River Watershed data bases. Software tools such as GIS,ARCMAP, Version 9.2 working with the Cedar River Watersheddata bases provided access to the required information to locateand size these “minutemen” retention basins with relative ease.




The example “minuteman” retention basin is shown in Figure 2-3. The basin is located in Franklin County and its locationrelative to the Cedar River Watershed is shown in red in the

upper right corner of Figure 2-3. The black line in the figure represents the ridge line for thedrainage area that feeds the stream that flows towards the topof the page. A culvert passing underneath the county roadprovides the location for a water gate to stop the flow at thatlocation and then store 30 acres of water at a three foot level.

- Note that in the example site location shown in Figure 2-3 thattwo other retention basins sites can be quickly identified, one oneach side of the example site!

- The software and computer screen interactive interfaceallowed the DNR technician to pull up a file containing the

elevation contours and with his computer screen scribe developthe ridge line “free-hand” for the example site sub-basin! Thenumber of acres within this sub-basin was readily availablewhen an inquiry was made of 996 acres.

- Earlier in Figure 2-1, it was indicated that the bulk of thewatershed area above Cedar Rapids has a gentle slope of 2%.

Several quick-looks within various sub-regions of the watershedgives strong indication that the 5800 “minuteman” retention



Figure 2-3

Example Retention Basin

defined in Franklin Countyusing existing Iowa DNR

software tools and

watershed data bases.



2. Step 2

The “how” of the Minuteman retention basins placedinto service!

• “Minuteman” retention basins are converted instantaneouslyfrom a planned row-crop land use or a grassland use farm landinto a flood water retention basin by the remote activation of awater flow control “gate” added as previously specified by theCW / NRBN design plan to an existing culvert in a road bed thatthen serves as a natural levee to retain a somewhat shallow (i.e.3-foot height of storage water) but large surface area aspresented by the natural topographical features of the area.See figure 3-1 for a diagram of this retention basindevelopment.





Figure 3-2

An example of the watershed

partitioned into sub-regions

Figure 3-2 shows the sub divisionof the watershed into small areas

shaped by how the drainage can

be separated and in this case, for

the measurements of nitrates in

drainage systems across the

watershed. Much flow data etc. isalready available because of this

previous work.



• 4. Step 3…Integration of new technology methods &hardware items

Explanation of how this CW/MRB system, incorporates newtechnology developments within the field of Hydrology,computers and related computational software and laserassisted topography mapping into the design and operationalcapabilities of this proposed system.

• Laser assisted topography mapping (LiDAR)A major contributor to the effectiveness of the CW/MRBN controlsystem for managing the flow levels within the Cedar River isthe accuracy of the input data that helps define the boundaryconditions upon which the hydrology model uses to synthesizethe interactive nature of precipitation interacting with thenature of the watershed as it moves along its drainage path tobecome a part of the river flow.

• The accuracy of the watershed topography mapping is one of these major contributors to the “confidence level” that this

control system will demonstrate in characterizing the flowbehavior of water within the watershed.• Current topography mapping data being used in determining

our presently defined 100-year flood plains for insurance claims,as well as the prediction of the behavior of runoff initiated atsome upstream location in the watershed with regard to its timeof arrival at some point downstream such as within the river

banks in Cedar Rapids, is based on mapping work done in 1950. The resolution of this data obtained by survey crews was simply




Figure 4-1(a) shows the resolution that this 1950s datahas on the hydrology models capability of defining thesub-region drainage time to a point downstream of Cedar

Rapids.

• The laser mapping technology, LiDAR, can provideelevation data as fine as +/- 4 inches and referenced toits location using a GPS-based coordinate system locationtechnique.

• Figure 4-1(b) shows how an improved hydrology modelcan add a greater resolution of drainage times for muchsmaller and more numerous sub-regions within theupstream watershed in reference to drainage times to thecity of Cedar Rapids.

Compare figure 4-1(a) to figure 4-2(b)!

• The LiDAR mapping technique was a Laser Interferometermeasurement tool along with GPS receivers mounted in alow flying airplane that collects an enormous amount of digital data as it maps regions of the watershed.








• Hydrology modeling, expanded computer software &computer computational through-put times, etc.

The above defined advanced technology developmentsare interrelated as they collectively add greater accuracyand resolution to output behavior parameters definingthe flow behavior of water across the total watershed.

• NEXRAD …A Doppler weather radar system already

deployed and in operation across eastern Iowa. See figure4-2 for a map showing the locations of these sensorsystems.NEXRAD was designed, built and now managed by theNational Weather Service Bureau of the federalgovernment.

Technology upgrades that continuously provide enhancedoperational capabilities and accuracies in providing“weather related” information across eastern Iowa arebeing done already.

• Much of the weather related data that can be segregatedby sub areas within the Cedar River watershed is already

being provided but is not being used in a comprehensivemanner to hel with flood-risk miti ation for the Cedar



Figure 4-2 Doppler Weather Radar Sensor Locations

Sensors covering the Cedar

River Watershed area. (Qty. 4)




• This Doppler weather radar system can “map” the totalCedar River watershed and can provide data, forexample, regarding precipitation intensity with respect to

time and cumulative amounts of specifically defined sub-regions within the watershed! This distributed dataacross the various defined sub-regions of the watershedis then, the primary input data that is needed by thewatershed developed “hydrology model” that simulatesthe behavior of the movement of water along its drainage

path within its sub-region and then become integratedinto a network for the combined response of the totalwatershed!See Figure 4-5

• Data from the sensing systems within the Doppler radar

are data that must also be “calibrated” to ensure thatthere is high correlation between, for example, therainfall in a sub-region that the radar system senses andthe actual amount of rainfall that fell in that sub region.

• The University of Iowa Hydrology department hasdesigned, produced and has in operation at numeroussites within the Iowa City area rainfall monitoring stations




• The U of I rainfall calibration systems are fully automaticin operation and data reporting and do so in remotelocations without any other support inputs such as power,

etc. These calibration stations are designed such thatthey can be easily moved across areas within thewatershed on a temporary basis as the calibration data isgathered for each sub-region. The automatic datareporting is accomplished by a computer controlledcellular phone link that reports as rainfall occurs in that

area. The monitoring station uses battery power withrefresh power provided by solar panels. Figure 4-3 is aphotograph of a U of I automatic rainfall monitoringstation currently in use in the Iowa City area. Figure 4-4shows the locations of monitoring stations currentlydeployed in the Iowa City area.

(Note: Citizens of Iowa City can learn of the monitoringstation located close to their home and can then call thestation’s phone number (for public use) and learn howmuch rain has fallen over a particular period of time!)

Figure 4-3



g

U of I Automatic Rainfall monitoring site for calibration of the NEXRAD Doppler

Weather Radar Rainfall Sensing and Reporting system. (i.e. Rainfall collection

basin, solar panel, cell phone antenna, and room for additional components,

battery, etc. below the flat panel.)



Figure 4-4 Locations of the U of I Automatic Rainfall Monitoring

stations in the Iowa City area.



Figure 4-5




Remote activation of automatic operation of

water control “gates” or valves at the numerousbut selective “minuteman” retention basinsacross the watershed is a major flood control

feature of this proposed system!(See figure 3-1 for an example installation of awater control gate in a road culvert.)

The operational control system and the supporthardware for the water control gates as shownin Figure 9-4 is similar in design and operationof that of the U of I automatic rainfallmonitoring unit shown earlier in figure 4-3

(We don’t need to re-invent the wheel!)





5. Step 4…How other cities have addressed floodcontrol in this manner!

Identification of where similar flood-prone watershedareas are already implemented and in operation using

these same similar guiding hydrology principles andcontrol methodologies.

• Flood control system using retention basins insouthwestern Germany (Management in Baden-Württenberg for the two river basins of the Rhine and

Neckar rivers)

–There are common features between the flooding issuesof the Cedar River watershed basin and that of theGerman river basin defined above. In both, thecommunities along their respective rivers have over-

developed adjacent to these rivers. Thisoverdevelopment has occurred both within a 100-yearflood plain as well as the flood water path as it movesthrough the various communities.

- However, in Germany the various affected communities

did not retreat within themselves and each triedseparately to solve these flooding issues by building

5 S 4 H h i i h dd d fl d l i



5. Step 4…How other cities have addressed flood control inthis manner!

- These German communities joined together within a particularriver basin and formed watershed flood managementorganizations and focused on more comprehensive solutionsthat were more cost affordable by this collective body of communities and their combined wealth was then betterinvested for the longer term, more permanent solutions to theglobal weather change impacts.

- This joint response planning did not require these Germancommunities to basically change the “historical face andcharacter” of their older parts of their communities.

- These German watershed flood management organizationswere one of the first to use the new hydrological technologytools now available that allows an active, real-time floodmanagement system be developed and managed that

incorporates upstream retention basins or reservoirs.

-A complete report describing this German solution isreferenced in figure 5-1 and can be accessed free of charge onthe web.

- Figure 5-2 is a map of this Baden-Württenberg watershed andthe locations of 34 new retention reservoirs integrated into theirflood-water mana ement lan.



Figure 5-1 Flood control system using upstream water retention basins in

Southwestern Germany. (Introduction of available report)



Fig. 2 Catchment area of Kocher-Lein (A) and upper Jagst

(B) (Table 1 and 2) with the locations of 13 flood control

reservoirs along the rivers Kocher (A) and Lein (tributary),

furthermore with 21 flood control reservoirs along the river

Jagst

Figure 5-2

Retention basins built in

the German watershed.



5. Step 4 – (Continued)

• Flood control system using upstream retentionbasins in the Hungarian part of the Tisza Riverbasin.

- A similar approach is developed in this riverbasin as described for the earlier definedGerman river basin for flood water managementat the watershed level by an association of

affected communities.

- See figure 5-3 for visual display of the TiszaRiver basin.



Figure 5-3 Map of the Tisza river basin in Hungary




• Flood control planning in ChinaChina has major water related problems that have become of acrisis nature. Too much water at times and not enough at othertimes. The problem was ignored for too long and now majornational wide directives are being ordered to try and recover.

The integrated approach to flood management in China is nowvery comprehensive and complex. Their national flood plan isbased on a three prong focus: (1) delineated flood plains, (2)flood storage through upstream retention basins and (3) floodprotected areas.

The advantage of upstream retention basins is also allowingChina to begin to better address water quality issues and verypoor land management practices; especially those related toexcess sediment in the surface run-off water.




5. p

• Water control system in California that usesupstream retention basins for preserving water forlater release for irrigation purposes.

Because the bulk of the watershed above Cedar Rapids has agentle slope of 2%, Iowa can learn from the water managementsystems and commercial hardware available and in use inCalifornia in routing water for irrigation in local areas that alsohave a gentle slope similar to the Cedar River Watershed.

• Vernon County in Wisconsin using upstream

retention basins for active flood mitigation.Vernon County is located in southwestern Wisconsin and has arugged topography with beautiful scenery. The county wassurrounded by glaciers approximately 12,000 years ago but wasun glaciated itself which left the rough topography. However,flooding was a growing problem until the Wisconsin legislature

established the PL 566 Coalition that provided the coordinationof a plan & funding that built 22 retention basins upstream of the troublesome rivers and streams to mitigate the flooding riskover a period of 15 years. These retention basins are verysimilar to the basins built in Germany as discussed earlier. Theaverage height of the basin levees was 39 feet and an average

levee length of 420 feet. These 22 retention basins createdwater storage of 19,132 acre-feet for a watershed area of

Quick-Look Cost Metric Comparison



Quick-Look Cost Metric ComparisonSummary:

Vernon County * Cedar River

WatershedWisconsin

above Cedar Rapids

Watershed Size 78,881 acres 4,166,400 acres

Storage Basin Capacity Required 19,132 acre-feet864,000 acre-feet

Total Initial Investment Cost $9 Million $129 Million

Yearly Ongoing Expense TBD $2 Million

Cost per acre-feet of storage $470 $149

Initial cost investment perAcre of watershed $126 $31

Yearly on-going expense per acre



Quick-Look Cost Metric Comparison Summary:



Q p y

“Minutemen” basinsCR Council Plan

Watershed CostCedar Rapids alone

Metrics:

Cost of initial investment per ace of totalWatershed above Cedar Rapids $31.00 $240.00

Cost per acre of developed retention basin $539.00

N/ACost per month per watershed citizenfor the next 30 years $1.03 N/A

Cost to maintain flood protection system perMonth per citizen of watershed (City of CR) $0.33 TBD

Cost per month per citizen of Cedar Rapids forthe next 30 years. N/A

$12.63

Cost per citizen of Cedar Rapids N/A

$4,545

Quick-Look Cost Metric Comparison Summary:



p y

continued “Minutemen” basins CRCouncil Plan

approach

Need to move back from the Cedar River, buy Only limitedLarge amount

out properties and establish “green space.” amount required required

Contained great risk to CR businessesand public buildings near river. No risk Some risk

Risk of obtaining money in timely fashion Within local Needfederal

to get plan in effect Control of Watershed help

Adds aspects for improved water quality and Building retention Noneprovides for improved land management basins already in

practices over the total watershed progress across Iowaby Dept. Of Agriculture

for nitrate run-off management

Allows Iowans along each major river Promotes a watershed Eachcity is on

watershed to come together and “harness” “system” approach! their

6 Step 5 Configure a system for the Cedar River



6. Step 5…Configure a system for the Cedar RiverWatershed using this new hydrology technology andestablished principles that mitigates future floodingalong the Cedar River

• Refine the number of storage acres of land north of CedarRapids that are required for the “minuteman” retentionbasins.In section 2. of this proposal, it was established on a generaloverview that 864,000 acre-feet of top surface storage wasrequired for “minuteman” basins.

In other Iowa DNR reports, it is indicated that the CedarRiver Watershed above Cedar Rapids will haveapproximately 1.2% of the watershed will be involved withrivers, streams and creeks that currently provide therequired drainage.

Therefore: ( 4,063,360 acres in watershed (.012) = 48,760acres in rivers,

north of Cedar Rapids,)streams and creeks.

The rivers, streams and creeks will automatically beconsidered capable of storing the addition of 3 feet of water

2. Continued



2. Continued

Therefore: 864,000 acre-feet of water storage = 288,000 acres of 3 feet of water storage

288,000 acres of 3 feet of - 48,760 acres in rivers = 239,240 acresof

water storage streams and creeks 3 feet of watercapable of handling storage

required.3 ‘ of water.

Expressed in the quantity of 60 acre-basins at 3 feet of water, the storage isdetermined to be a quantity of 3,987 basins.

If we divide the total Cedar River watershed into a quantity of 8 sub-areas,then we can for this example, assign an equal number of basins to eachsubarea.(Also, the boundaries of these sub-areas could be established such that thisassignment was correct.

3,987 qty of 60 acre/3 feet500 qty of 60 acre / 3 feet of per sub-areaof water storage water storage

8 sub areas(This could also be expressed as a quantity of 350 – 60 acre / 3 feet basinsand quantity of 300-30 acres / 3 feet basins. This would be a totalquantity of 650 “minutemen” basins per sub area.)

For Field-Tile drainage areas, it is estimated for this example thatapproximately 400 field-tile drainage fields per sub-area of the watershed



2. Continued• In structuring the sub-areas within the Cedar River

Watershed, let us assume that the sub-area drainage flowsystem would be that described in Figure 6-1.

• Figure 6-2 is a proposed Control Data-Link andorganizational network for the quantity eight sub-areas.

- The control center has dynamic control over the entirewatershed

- Other observation centers can be located throughout thewatershed as considered necessary for possible back-ups

control delegation from the control center.

- Periodic inspections, maintenance tasks and emergencyactions required on the sub-area level with responsibilitiesassigned throughout the watershed at the countytownship level. Required funding will be created at the

total watershed level for any required actions.







7. “Wetlands” Incorporation into the CW/MRBN flood

control system for the Cedar River watershed.

• There have been recent efforts within Iowa to return to

“wetlands” a number of acres of land that are not proving to beprofitable as farm land or grazing land for livestock.

• Government funding has been proposed to purchase this landand return it to its more natural condition within nature of thatas a wetland status.

• Approximately ____ acres have been identified by their ownersthat they are more than interested in removing this type of landfrom production farming.

• Many of these acres ( _____ acres) are located within the CedarRiver watershed and would easily serve as more “permanent”

retention basins that would also be able to store additional floodwater as the need would arise.

• These wetlands can help restore many features of our state’snatural ecology regarding for example, the quality of water inour streams and rivers as well as help restore our state’svarious water tables and the major aquifer that maps beneaththis state.



8. Reimbursements to the land owners for the

development of these “minutemen” retentionbasins on their property.

• Any reimbursement to the owners for the permission touse their land for these “minutemen” retention basinsmust be revenue neutral to the general citizens of thestate.

• Like our European friends addressing flood mitigation at awatershed approach level, watershed associations shouldbe formed consisting of the communities and citizenswithin that watershed. These associations must berepresentative bodies that can determine methods forraising revenue to pay for any reimbursement plan that isdeveloped to ensure that land owners are not financially

penalized for having the possibility of having someportion of their land flooded for several weeks in thespring of the year, every 15-20 years.

• It is recommended that these land owners should benefiteach year for agreeing to have these “minutemen”

retention basins located on their land. This could be doneb a ro ert tax relief that a ain would be covered b



8. Reimbursements (Continued)

•In those years that flooding does occur, theseland owners would receive a financial paymentfrom the watershed association to make up forthe lost production revenue, lost due to thedeliberate flooding of their land to protect thecommunities downstream. Also, any additional

damage to the land that occurs during thisdeliberate flooding should also be covered insome equitable fashion.

• The watershed associations should perceive this

request for raised revenue as a form of insurance with the higher fees being borne bythose having the higher risks had a floodoccurred. However, all citizens living within thiswatershed should also contribute to this

revenue fund to help protect their quality of lifeissues associated within the community in



9. Required Water Flow Control Hardware items, vendors,

contractors and remote control features needed for this“minutemen” retention basin approach.

• The simplicity of the design features associated with thedevelopment and integration of these “minutemen”retention basins into the natural topographical features of the Cedar River Watershed allows for a moderate cost tothe citizens of this watershed.

• Numerous small business contractors will have thecapability on day 1 to compete for these installationcontracts. Farmers that may have access to a backhoewill be able to install these retention basis features,perhaps on their own farms!

• The new electronic hardware items required are currently“off the shelf” type of items that may only need to bepackaged in a container for protection from theenvironment. Commonality of these special hardwareitems also allows for a moderate cost to the citizens of

this watershed. These electronic hardware/software itemscan be design integrated, packaged and produced by



2. Continued

• Reusable water control concrete bulkhead items across

the numerous retention basin locations allows for thesecomponent items to be built off-site and hauled to theparticular site.

• Water control gates (or shut off valves) as a majorcomponent of this retention basin concept. The design

integration of this water control gate function into aconcrete culvert-type design and manufacturing processalso shows great promise in the cost containment of these integrated water gate features. An Iowa concreteproducts company has participated with counsel on thisdesign.

• Earlier in this proposal, Figure 3-1 showed a typicalintegration of a “minuteman” retention basin in to theupper Cedar Watershed with a levee system alreadyprovided by the existing drainage structure. Figure 9-1shows more design detail on the type of prebuiltcomponent items needed at each retention basin.

Fi ure 9-2







2. Continued

• Additional features of the component that integrates the

water control gate feature into a modified concreteculvert-type design is shown in Figure 9-3. It is proposedthat only one or two sizes of this component will beneeded by having adaptable features in other parts.

• Figure 9-4 shows additional design detail and defines the

electronic-type components needed to make the watergate remote controllable. Similar design features arealready in use and were discussed earlier in section 4 of this proposal and shown in Figure 4-3.

• Figure 9-5 is an example of the numerous types of water

control gates that can be purchased from a number of vendors on the international market.

• Numerous Iowa concrete contractors and suppliers arealso available to compete and build the proposedcomponents shown in Figure 9-1.









2. Definition and estimated cost of a “feasibilityconfirmation” study regarding this

“minutemen” retention basin concept for floodmitigation in the Cedar River Watershed.

(Commentary: Within the last ten years or less,significant developments in hydrology technology

science, LiDAR watershed topography mapping detail andaccuracy, adapted computer software and watershedhydrology modeling, NEXRAD Doppler weather radarrainfall measurement sites already installed in theeastern Iowa area (and not fully used within itscapabilities currently), cell phone site coverage, and off-

the-shelf remote control system hardware items makethe technology risk in this approach almost nil. Theproblems of this approach may well be more in the areasof “political will” and how fair the cost and impact of thisinstallation is perceived by the citizens bearing the costof this flood risk mitigation effort)



2. Continued

The hydrology department at the University of Iowawould use this study opportunity to do the following

tasks:1) Propose a network control system to allow the remote controlof these numerous retention basins and field-tile drainage areawater gates and estimate the projected design anddevelopment costs of this system.

2) Provide cost and design related information for the U of IAutomatic Rainfall Monitoring System hardware components tobe purchased for use in the Cedar River watershed. Also,calibrating the NEXRAD system for the watershed.

3) Provide a design approach and the estimated cost of thecalibrating the new hydrology modeling developed for the CedarRiver watershed.

4) Provide some consulting counsel to other contractorsincluding the Iowa DNR.

5) An estimated performance schedule is required for each

element of their cognizance in the actual final design.



2. Continued

• The Iowa DNR would provide a quick look risk assessmentof locating the required number of acre-feet of waterstorage in the upstream watershed. The Iowa DNR wouldalso estimate the cost of developing the retention basinlocations and the mapping of these retention basins andthe listing of the level of water storage of each separatebasin site.

• The Cedar Rapids Watershed Subcommittee, under thecounsel of Rebuild Iowa committee member, Bill Bywaterand Senate leader of the Iowa Senate Rebuild Iowa

Committee, Senator Rob Hogg, is to collect contractorestimates for the design and manufacturing of theseveral reusable components defined in brief in Figure 9-1 of this proposal.

• The Cedar Rapids Watershed Subcommittee would alsoobtain contractor estimates for the actual “typical”



2. Continued

• The Cedar Rapids Watershed Subcommittee isto collect the initial “quick look” study cost andprovide this cost summary to both CommitteeChairman Bill Bywater and Senator Rob Hoggfor further action with our state and communityleaders including Cedar Rapids, Waterloo, CedarFalls, Mason City and others.

• This “Feasibility Confirmation” study will alsoprovide greater resolution of design detail andrelated costs of the total actual Cedar RiverWatershed design and installation costs of this“minuteman” retention basin.

• A target cost goal for this “FeasibilityConfirmation” quick look study is set at$10,000.



2. What is an initial “quick look” estimate of this total program to have it designed,implemented and on-line ready to go?

Rough “ballpark” cost estimates for all phases of this concept including:

1) Design, calibration, construction and implementationcosts.2) Year to year operating costs

3) Year to year maintenance costs4) Cost of escrow account to cover the yearly incentivepayments to the landowners for allowing the retentionbasins on their land(i.e. property tax relief on those areas)

5) Cost of escrow account to cover the crop revenue lossfor the year when it becomes necessary to flood theretention basin sites.6) Bonding costs for the purchase of 50-year bonds at 3%investment return to pay for the initial design,construction and implementation costs. (One timebonded expense).

7) Total “ballpark” cost estimate summary.

11. Continued:



(1.1) Detailed designs defined and estimatedcosts listed:

a) Hydrology, modeling, model calibration, NEXRADrainfall sensor/area calibration, LiDAR mapping study andintegration, network control and management systemdesign and simulation evaluations, cell phone control andmanagement system.

Estimate: $4,000,000

b) Watergate design (incorporated with the concreteculvert design)

Estimate: $ 10,000 (includes concrete

mold frames)

c) Remote control / activation hardware design (tile fieldsincluded)

Estimate: $21,000

d) Desi n of concrete bulkheads (Consider 5 different

11. Continued:

(1 2) C t ti t i l di h t f ll



(1.2) Construction costs including purchase costs of allmaterials supplied. (Average cost per “minuteman”retention basin)

Including: Controller, water level sensor, cellular phone, modem

solar energy system, battery, water gate actuator system(motor, gear, reduction unit), concrete water gate, concretebulkhead, adapter sleeve, security fencing, debris guard, fieldtile water gate, security and debris protection.

Retention basin:

Watergate controller & actuating system $4,300

Concrete water-gate, qty (1) $ 1,500

Concrete bulkhead, qty (1) $ 850

Security & debris protection $ 600

Installation costs $4,000

Water level sensor, qty (1) $400

Basin Total:$11,650

(1.3) Total Summary of all one-time cost



items:

(1) Material costs & installation costs for qty:

5200 separate “minutemen” retention basin complex…$60,580,000

(2) Material costs & installation costs for qty:3200 Field tile gate units…

$19,840,000

(3) Hydrology design expenses (See section 1.1(a)$4,000,000

(4) Watergate design (See section 1.1(b) ) $

10,000

(5) Remote control design/communication link design

(See section 1.1(c) ) $ 21,000

(6) Concrete bulkheads design (See section 1.1(d) )

$ 14,000

11. Continued:



(2) Year to year operating costs$50,000 (3) Year to year maintenance costs $

5,000(4) Cost of escrow account to cover yearly incentive

to participating landowners:

i.e. 239,000 acres in retention basins, in watershed

- 23,040 acres in wetlands, in watershed

216,200 acres eligible for incentive payments

(216,200 acres) ($5 / acre incentive) =$1,081,000

(5) Cost of escrow account to cover drop revenue loss for$345,920

years of flooded retention basins. Probability of flood risk

(500 year floodprevented is considered here:yearly escrow payment)

500 year flood risk would require that all 216,200 acres of retention

basins to be flooded and lost to farming.

11. Continued:



A more conservative risk mitigation decision taken is touse a flood

recurrence frequency of 200 years instead of the stated500 year flood levels.

Census data shows approximately 516,000 citizens in thewatershed.

69,184,000

(516,000 citizens ) = 0.67 cost per year perwatershed citizen

(200 year risk cycle) or $345,920 per year watershedcost.

11. Continued:



(5) Continued

30-year flood risk level. This would require the use of

25% of the acresin the retention basins.

The crop production loss would be

(25%) (216,200 acres) (80 bushels-acre) ($4.00 - bushel)

equals: $17,296,000

Yearly costs for this risk mitigation is as follows:

($17,296,000) = $1.12 per year per citizen

(516,000 citizens) (30 year risk cycle)$576,533

(30-year flood

escrow payment)

11. Continued:



(5) Continued

30-year flood risk level. This would require the use of

25% of the acresin the retention basins.

The crop production loss would be

(25%) (216,200 acres) (80 bushels-acre) ($4.00 - bushel)

equals: $17,296,000

Yearly costs for this risk mitigation is as follows:

($17,296,000) = $1.12 per year per citizen

(516,000 citizens) (30 year risk cycle)$576,533

(30-year flood

escrow payment)

11. Continued:



(6)

Bonding expense for the purchase of 30-year bonds at3% interest to pay for the one time costs of this flood

mitigation concept of $85,000,000.

Total loan interest expense: $ 44,010,834

Total amount paid: $129,000,834

or $4,300,028 per year for

30 years, watershed cost

or $8.33 per year per citizen

in watershed for 30 years

• Continued: Total “ball park” cost estimate summary:



(1) Design & installation costs $85,000,000

(2) 30-year bond & total interest expense $44,010,834

30-year total debt of $129,000,83430-year Bonds sold @ 3%

Yearly expense for 30 years $4,300,028

or $8.33 per year per

citizen in watershed for 30 years.

(3) Yearly on-going expenses $2,058,453or $4.00 per year per citizen in

watershed on-going.

$12.33 per year per citizen in

watershed

for 30 years… and then it

becomes:

$4.00 per year per watershedcitizen.

C o s t p e r m o n t h

p e r w a t e r s h

e d c i t i z e n

$Loan Start 30 years Future years

Time

$1.03 per month per watershedcitizen for 30

years.

0.33 per month per citizen continuous forward

1) Proposed Schedule of milestones leading to a fully operational



) p g y p

“Minutemen” retention basin network for flood control and Water Quality

Control on the Cedar River.

Milestone

[1] The passage of legislative authority guidelines for the formation of specificmajor river watershed associations across the state with bonding authority

that allows use of the State of Iowa bond rating level, but imposing these

expenses only on the citizens of each respective watershed association.

(This was done in Europe in Germany and Hungary. We may be able to

use their statutes as a guide in the formation of our own policies.)

[2] Formation of the Cedar River Watershed Association with representative

members from across the watershed as specified by the statutes defined in

milestone [1] above.

[3] The Iowa Legislature and executive branch to designate funding for theconversion of additional land, at the bequest of the owners, into “wetlands.”

There is a one time re-numeration to the owner for this classification change.

These new wetland acres will greatly help in the improved management of the

watershed at all levels of concern.



Milestone



[5] Funds identified for Feasibility Confirmation Study. Use partial funds to

develop cost budget for the total program.

[6] Sale of Watershed Association Bonds to raise required design, calibration,

simulation and implementation

[7] Identification of partial, initial funding to jump start the hydrology study and

modeling development.

[8] Hardware Component design completed.

[9] Basin locations, configurations and water storage capability determined.

[10] Installation of the remote control water gates and other sensors.

[11] Integrate and test the complete network system.



Water control proposal for Cedar Rapids area

Documents