GREAT LAKES/ATLANTIC REGION

7322 Newman Blvd., Bldg. 2

Dexter, MI 48130

(734) 623-2000 www.ducks.org

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Table of Contents Introduction Project Location Site Characteristics Pre-development Conditions Post-development Conditions Post-development Conditions Embankment Design Subsurface Drainage Tile Modification Sedimentation Analysis Use of County Roads Floodways, Floodplains, and Wetlands Runoff Analysis Watershed Time of Concentration Precipitation Model Runoff Model Runoff Conveyance Hydraulic Model Summary & Conclusions

(Appendices listed on next page)

Dexter, MI 48130

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Appendix HydroCAD Report – Existing Conditions .................................................................................. A-1 HydroCAD Report – Proposed Conditions................................................................................. A-2 StreamStats Report...................................................................................................................... A-3 Drainage District Map................................................................................................................. A-4 Watershed Characteristics ........................................................................................................... A-5 Sheet Pile Calculations ............................................................................................................... A-6 NRCS Soil Report ....................................................................................................................... A-7 NRCS Hydrologic Soils Report .................................................................................................. A-8 Tile #1 Calculations .................................................................................................................... A-9 Sediment Accumulation Calculations ....................................................................................... A-10 FEMA Flood Map ..................................................................................................................... A-11 FWS Wetland Inventory Map ................................................................................................... A-12

Dexter, MI 48130

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Introduction

This constructed wetland project is located in Emmet County, Iowa just South of Iowa Lake. The constructed wetland site is situated on two different property owners: 1) Neary Family Farms and 2) Iowa Department of Natural Resources (IADNR). The constructed wetland site is currently in an existing wetland bottom area that does not consistently hold or maintain water. The existing wetland is predominately on the DNR property, however, this project requires the participation of Neary Family Farms due to a portion of the normal water level (NWL) and 100-year storm bounce extending onto the Neary Family Farm property.

Based on our on-site survey and hydrologic resources, the site exhibits a watershed of approximately 1,557.15 acres that routes into the proposed wetland area before routing to Iowa Lake. The land is currently primarily used for public recreation and conservation. A portion of the land on Neary Family Farms within the 100-year storm bounce area is currently being row cropped. The plan is to use the constructed wetland area primarily for water quality, recreation, and the intention of promoting wildlife on the site.

This wetland is planned to provide nutrient reduction benefits. Nitrates will be converted to nitrogen gas through natural processes as the water passes through the wetland. Sediment with phosphorus will also be captured but will need to be removed from the sediment basin(s) on a regular basis.

The site was initially assessed by using remote digital desktop information to see if a wetland at this location was feasible. Payment information was presented to the landowner(s) who expressed interest in participating with this project.

The wetland has been designed using the requirements outlined in NRCS Conservation Practice Standard (CPS), Constructed Wetland, Code 656 (December 2023). The project will include a constructed wetland using a sheet pile weir, berm, and two submerged berms. One tile line will be modified to divert water into the wetland. There are multiple tile that are currently out-letting into the ditch West of the wetland that already outlet at least one foot above the NWL.

The project is a Job V Classification as determined by the Iowa Engineering Job Approval Authority Form IA-ENG-6 (March 2019). Since the wetland primary design standard is CPS 656, Constructed Wetland, and the wetland falls under “Field Runoff Treatment”, with a drainage area over 1,000 acres, Job Classification V applies. The Job Classification V is still satisfied with the secondary design standard, CPS 410, Grade Stabilization Structure, since the effective height is less than 35 feet.

IADNR will submit permits for this project, which will include obtaining permits from The State Historic Preservation Office (SHPO), The Army Corps of Engineers, and the Iowa Department of Natural Resources (DNR), and the local Drainage District.

The permanent easement for this project will be on one landowner – Neary Family Farms. An easement will not be provided on the IADNR land. We will be updating the abstract and will have a signed easement recorded for the area as shown on the attached site plan drawing. One 10" tile will be daylighted and allowed to surface flow to the wetland.

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Proposed work includes:

1) Create berm to impound water within the wetland area, 2) Provide sheet pile primary weir within berm, 3) Daylighting one tile into the wetland, 4) Provide submerged berms for water retention,

5) Provide water control structure for water management, and 6) Seeding and restoration of disturbed areas.

Project Location

Site Characteristics

Pre-Development Conditions

Pre-development conditions for the work area include the uses described in the previous section, which is predominately an agricultural landscape. The surrounding areas outside the work area are mostly grain production agricultural, row crops, but also include pastures and some timber. Mild topography is predominant in the area with small waterways, drainage ditches, and culverts. The majority of ground cover is row crops during the growing season with a combination of row crop residue, tillage areas, and cover crop during non-growing season months. Soil types in the area vary with dominant hydrologic soil group D. Hydrologic soil group D is known to have a slow infiltration rate resulting in high runoff potential when wet. A NRCS Soil Map for Hydrologic Soil Groups within the Area of Interest is located in the appendix of this report. The Area of Interest (AOI) is shown on the NRCS Soil Report and NRCS Hydrologic Soil Report.

Dexter, MI 48130

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Post-Development Conditions

Post-Development conditions will remain the same as pre-development for the basin tributary to the wetland area. This project includes grading within the wetland area itself (sedimentation basin) and creating a berm at the downstream end of the wetland. None of the proposed work will change the tributary area or runoff characteristics of the basin.

It should be noted that the primary design standard for this project is the NRCS CPS, Constructed Wetland, Code 656 (December 2023). The definition of this standard is, “An artificial wetland ecosystem with hydrophytic vegetation for biological treatment of water.” Since the sheet pile weir will be a full flow open structure, NRCS CPS 410, Grade Stabilization Structure (January 2023), is the standard utilized for designing the primary weir and berm.

Embankment Design

CPS 410, Table 1 – Design Criteria for Establishing Minimum Capacity of Full-flow Open Structures was utilized in the design of the embankment and spillway. The Classification initially considered is “All Others” with Drainage Area greater than 900 acres and/or a Vertical Drop greater than 10 feet.

This classification requires a minimum storm design frequency of 25 years for the principal spillway capacity, and a storm design frequency of 100-years for the Total Capacity (24-hour duration storm).

CPS 656 also requires the impoundment to have sufficient capacity to handle the peak flow and runoff volume from the 25-year frequency, 24-hour duration storm without overtopping the embankment, and provide erosion protection for the perimeter embankment. This criterion is met with the design, which is able to pass a 100-year storm through the sheet pile weir, while still providing 1-foot of freeboard.

The wetland design exhibits a water storage capacity of 116.061 acre-feet associated with the top of dam contour. The top of dam elevation is 1209.0ʹ and the downstream toe of the dam at the lowest elevation of the outside limit of the dam is approximately 1200.0ʹ. Accordingly, the vertical distance between these two points is 9.0ʹ. Since the water storage capacity associated with the top of dam is greater than 50 acre-feet and the height of the dam is greater than 6 feet, this wetland is considered a jurisdictional dam by Iowa DNR dam safety criteria.

The design criteria for Iowa DNR dam safety for Low Hazard Dams is providing a principal spillway designed for a Q10 (10% probability occurrence per year) without engaging an auxiliary spillway, and then to be able to withstand a Q100 (1% probability occurrence per year) without overtopping the dam. The principal spillway (sheet pile weir) was designed to route a 100-year storm event without an auxiliary spillway. This design criteria satisfies both the NRCS guidelines and the Iowa DNR dam safety criteria.

The sheet pile weir spillway exhibits a 90 feet wide crest with sidewalls that slope up 2:1. The 25-year storm bounce in the wetland is 1206.63ʹ and the 100-year storm bounce in the wetland is 1208.00ʹ.

The sheet pile sidewalls are designed at 1208.00ʹ, in accordance with CPS 410 design criteria (sidewalls set 0.5ʹ higher than the water surface attained by the principal spillway design discharge and at or above the maximum water surface attained by the total capacity design discharge). The top of embankment was set 1 foot higher than the sheet pile sidewalls (1209.00ʹ). The top of dam contour (1209.00ʹ) does extend onto the neighboring property to the Southeast but is contained within the

Dexter, MI 48130

6 | P a g e existing drainage ditch. A temporary water storage permit is planned to be acquired from this landowner.

Based on the Iowa Administrative Code (IAC), Chapter 73, the proposed dam is considered a low hazard dam. Specifically, Section 73.4(1) states, “Low hazard. A dam shall be classified as “low hazard” if failure of the dam would result in no probable loss of human life, low economic losses, and low public damages. Based on our review of aerial imagery, on-site inspections, and engineering analysis, the low hazard dam classification is satisfied due to the downstream area of the proposed wetland being approximately 1,100 acres of interconnected lakes primarily surrounded by wildlife areas. There are some houses located along certain portions of Iowa Lake northeast of 570th Avenue, however, even with an entire breach of dam (using the water storage to the top of dam), with instantaneous routing of water from the wetland into the lakes, the lake system would rise approximately 0.1 feet, which would have no adverse impact on the surrounding areas. Furthermore, in the event of an actual breach, water would be controlled by the channel between the wetland and the lake, which would cause the water rise in the lake system to be even less than 0.1 feet.

The foundation preparation of the dam includes site preparation 12 inches below the existing grade for the entire footprint of the dam. Additionally, a core trench will be excavated an additional 3 feet beyond the site preparation along the alignment of the dam for a distance and width, as shown in the construction plans and details. A clay core will be built back from the core trench and up to an elevation equal to the normal water level of the wetland (1202.2'). The clay core material will be compacted using NRCS Method 2, which includes two (2) complete passes of a tamping-type roller made over each layer. The maximum thickness of a lift of fill before compaction shall be 9 inches, unless otherwise indicated on the drawings. The roller shall be capable of exerting a minimum of two hundred (200) pounds per square inch. After the clay core has been constructed, suitable, cohesive material will then be compacted in lifts to an elevation 6 inches below the top of berm elevation. The general berm fill material will be compacted using NRCS Method 1, which includes placing earthfill so that the wheels or tracks of the loaded, hauling equipment, traveling in a direction parallel to the centerline of fill, pass over the entire surface of the layer being placed. Low ground pressure vehicles shall not be used for this purpose. Then, the final lift will be made with topsoil to the top of berm design elevation. The berm will be overbuilt in the field by 5 percent in elevation.

No structural calculations are necessary for the dam design except for the steel sheet pile spillway structure. These calculations are shown in Appendix A-6 of this report. Certain conservative assumptions were made on the soil conditions at the sheet pile structure location, in conjunction with the Iowa NRCS Standard Drawing 1411 (IA-1411) – Steel Sheet Pile Drop Structure (August 2010).

This NRCS standard drawing was also utilized in sizing the stilling basin downstream of the berm and spillway.

Two submerged berms have been designed perpendicular to the flow direction in the wetland in order to maximize residence time and increase hydraulic efficiency. These submerged berms are designed with 10-foot-wide tops at elevation 1201.7ʹ (6" below the NWL), provided with 3:1 side slopes.

An auxiliary spillway was considered and not implemented into this design due to the existing topography. The existing topography exhibits two small “hills” on each side of the natural outlet area for the wetland location to Iowa Lake. Due to these hills on each side of the outlet, significant excavation (and tree removal in a wildlife management area) would be required to construct an auxiliary spillway. Accordingly, the primary sheet pile weir was designed to be a full flow structure and accommodate a 100-year rainfall event with one foot of freeboard, without an auxiliary spillway.

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Subsurface Drainage Tile Modification

DU performed a tile investigation at the subject property in order to measure location and elevation of multiple known tile, as well as to determine if other tile exist on the property. The result of our investigation is shown in the engineering plans. DU located all known tile and other unknown tile.

Modifications to these tile were designed in order to outlet drainage tile inverts at least one foot above the NWL (1203.2ʹ), or else, divert the tile around and downstream of the wetland. Existing pipe flow rate capacities were matches or exceeded with all tile modifications, which is shown in the appendices of this report.

Sedimentation Analysis

DU analyzed the sedimentation accumulation anticipated for this site, which is included in the appendix of this report. Based on our analysis, the wetland would be expected to fill in with sediment after approximately 40 years. Accordingly, a 50ʹx100ʹ sedimentation basin has been designed for this site at the upstream end of the wetland at the main waterway. The sedimentation basin will allow for periodic maintenance and for removing of sediment captured prior to entering the wetland, which will extend the life of the wetland.

Usage of County Roads

There will be no planned usage of county roads except for when the contractor mobilizes to the site, as well as for hauling materials (rock, grout, etc.).

Floodways, Floodplains, and Wetlands

FEMA Map Number 19063C0250C, located in the appendix of this report, shows the existing wetland and channels within Zone A. Zone A refers to areas within the Special Flood Hazard Area (SFHA) 1% annual chance flood that do not have listed Base Flood Elevation (BFE). No portion of the project area is located within a Regulatory Floodway. The location of the berm was placed in a location of the existing basin where there is not a defined channel.

The U.S. Fish and Wildlife Service National Wetlands Inventory Map located in the appendix of this report shows “Freshwater Emergent” wetland in the basin and channels, and “freshwater” pond in the middle/bottom portion of the basin. As discussed above, the berm was placed in a location of the existing basin where there is not a defined channel.

Runoff Analysis

Watershed

Tributary area to the wetland area is determined to be 1,557.15 acres. This basin was determined with the aid of StreamStats which is a web-based Geographic Information System (GIS) application made available by the United States Geological Survey (USGS). Drainage District and topographic maps were also utilized in order to determine the watershed area. The basin area and other basin characteristics provided by the StreamStats application were reviewed prior to being referenced for this project. A watershed map and StreamStats informational report are included in the appendix of this report.

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Time of Concentration

Time of Concentration was calculated using the NRCS Lag Method which is appropriate for this watershed due to is rural character and long hydraulic length. Flow length of the watershed is shown on the watershed map in the appendix of this report, which was derived from StreamStats. NRCS Lag Method considers the flow length, average watershed slope, and maximum potential retention which is a factor of the SCS curve number (CN). Flow length, average watershed slope, and CN used for runoff analysis for this watershed are listed in the HydroCAD Report in the appendix. The average slope of the entire watershed taken from LiDAR data (3.20%) was utilized in this analysis.

Precipitation Model

The rainfall events and intensities were obtained from the HydroCAD for Emmet County, Iowa, MSE, 24-hour, Storm Curve 4 (MSE4). These rainfall events were compared to the MSE 4 rainfall intensities provided by Title 210, National Engineering Handbook, 2nd Ed., Amend. 1, July 2021, Figure IA2- 25, Wright County, NOAA 14 Rainfall Type MSE4. The HydroCAD Report in the appendix reflects the precipitation model and rainfall intensities for MSE4.

Runoff Model

SCS TR-20 NRCS Peak Flow method was utilized as a runoff model. SCS methods combine land use and soil type into a single parameter known as the Curve Number (CN). Based on the various land uses and the hydrologic soil groups (predominately HSG D) within the watershed discussed earlier in this report, a weighted CN of 84 was determined to be appropriate assuming straight row crops plus crop residue in good condition.

Runoff Conveyance

Hydraulic Model

HydroCAD 10.20-2g was utilized to model the watershed. Input parameters include watershed size, SCS CN (determined by land use and soil types), time of concentration calculations, precipitation input, stage-storage, discharge, and outlet details. The watershed was modeled with the proposed berm and principal spillway. The HydroCAD Hydrograph Report is included in the appendix.

Summary & Conclusions

This project does not change the natural drainage area, drainage courses, runoff coefficients, or any other characteristics of the watershed. A berm will be constructed at the downstream end of the wetland, which will be designed to accommodate a 100-year design storm without affecting neighboring properties. Significant benefits to the wetland area and areas upstream of the wetland area include improving water quality, promotion of wildlife habitat, as well as a nutrient and sediment buffer.

Dexter, MI 48130

LEADER IN WETLANDS CONSERVATION

Appendix A-1 HydroCAD Report – Existing Conditions

1S

Watershed Upstream of

Culvert

3S

Watershed Downstream of Culvert2P

560th Ave Culvert

4P

Existing Wetland

Condition

Routing Diagram for IA-340-13 - Neary - Existing Condition - Simplified Further

Prepared by Ducks Unlimited HydroCAD® 10.20-2g s/n 04207 © 2022 HydroCAD Software Solutions LLC

Subcat Reach Pond Link

IA-340-13 - Neary - Existing Condition - Simplified Further Prepared by Ducks Unlimited

Page 2HydroCAD® 10.20-2g s/n 04207 © 2022 HydroCAD Software Solutions LLC

Project Notes

Copied 10 events from IOWA-SHEY 9-27-23 24-hr S1 storm

Rainfall events imported from "NRCS-Rain.txt" for 1454 IA Kossuth

Rainfall events imported from "NRCS-Rain.txt" for 1454 IA Kossuth

Rainfall events imported from "NRCS-Rain.txt" for 1431 IA Emmet

Rainfall events imported from "NRCS-Rain.txt" for 1431 IA Emmet

Rainfall events imported from "NRCS-Rain.txt" for 1431 IA Emmet

Rainfall events imported from "NRCS-Rain.txt" for 1431 IA Emmet

Page 3HydroCAD® 10.20-2g s/n 04207 © 2022 HydroCAD Software Solutions LLC

Rainfall Events Listing (selected events)

Event# Event

Name

Storm Type Curve Mode Duration

(hours)

B/B Depth

(inches)

AMC

1 10-Year MSE 24-hr 4 Default 24.00 1 4.43 2

2 25-Year MSE 24-hr 4 Default 24.00 1 5.57 2

3 100-Year MSE 24-hr 4 Default 24.00 1 7.69 2

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Area Listing (all nodes)

Area

(acres)

CN Description

(subcatchment-numbers)

1,557.150 84 Weighted Average (1S, 3S)

1,557.150 84 TOTAL AREA

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Soil Listing (all nodes)

Area

(acres)

Soil

Group

Subcatchment

Numbers

0.000 HSG A

0.000 HSG B

0.000 HSG C

0.000 HSG D

1,557.150 Other 1S, 3S

1,557.150 TOTAL AREA

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Ground Covers (all nodes)

HSG-A

(acres)

HSG-B

(acres)

HSG-C

(acres)

HSG-D

(acres)

Other

(acres)

Total

(acres)

Ground

Cover

Subcatchment

Numbers

0.000 0.000 0.000 0.000 1,557.150 1,557.150 Weighted Average 1S, 3S

0.000 0.000 0.000 0.000 1,557.150 1,557.150 TOTAL AREA

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Pipe Listing (all nodes)

Line# Node

Number

In-Invert

(feet)

Out-Invert

(feet)

Length

(feet)

Slope

(ft/ft) n Width

(inches)

Diam/Height

(inches)

Inside-Fill

(inches)

1 2P 1,226.36 1,226.36 25.0 0.0000 0.012 72.0 60.0 0.0

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Notes Listing (all nodes)

Line# Node

Number

Notes

1 Project Copied 10 events from IOWA-SHEY 9-27-23 24-hr S1 storm

2 Rainfall events imported from "NRCS-Rain.txt" for 1454 IA Kossuth

3 Rainfall events imported from "NRCS-Rain.txt" for 1454 IA Kossuth

4 Rainfall events imported from "NRCS-Rain.txt" for 1431 IA Emmet

5 Rainfall events imported from "NRCS-Rain.txt" for 1431 IA Emmet

6 Rainfall events imported from "NRCS-Rain.txt" for 1431 IA Emmet

7 Rainfall events imported from "NRCS-Rain.txt" for 1431 IA Emmet

MSE 24-hr 4 10-Year Rainfall=4.43"IA-340-13 - Neary - Existing Condition - Simplified Furt

Page 9HydroCAD® 10.20-2g s/n 04207 © 2022 HydroCAD Software Solutions LLC

Time span=0.00-48.00 hrs, dt=0.05 hrs, 961 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN

Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method

Runoff Area=899.170 ac 0.00% Impervious Runoff Depth=2.75"Subcatchment 1S: Watershed Upstream Flow Length=11,480' Slope=0.0320 '/' Tc=109.9 min CN=84 Runoff=866.81 cfs 206.334 af

Runoff Area=657.980 ac 0.00% Impervious Runoff Depth=2.75"Subcatchment 3S: Watershed Flow Length=7,292' Slope=0.0320 '/' Tc=76.4 min CN=84 Runoff=816.20 cfs 150.988 af

Peak Elev=1,235.54' Storage=5.743 af Inflow=866.81 cfs 206.334 afPond 2P: 560th Ave Culvert Primary=397.66 cfs 158.433 af Secondary=457.42 cfs 47.901 af Outflow=855.07 cfs 206.334 af

Peak Elev=1,205.18' Storage=45.707 af Inflow=1,520.50 cfs 357.322 afPond 4P: Existing Wetland Outflow=1,411.67 cfs 357.297 af

Total Runoff Area = 1,557.150 ac Runoff Volume = 357.322 af Average Runoff Depth = 2.75" 100.00% Pervious = 1,557.150 ac 0.00% Impervious = 0.000 ac

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Summary for Subcatchment 1S: Watershed Upstream of Culvert

Runoff = 866.81 cfs @ 13.49 hrs, Volume= 206.334 af, Depth= 2.75" Routed to Pond 2P : 560th Ave Culvert

Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-48.00 hrs, dt= 0.05 hrs MSE 24-hr 4 10-Year Rainfall=4.43"

Area (ac) CN Description

* 899.170 84 Weighted Average

899.170 100.00% Pervious Area

Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs)

109.9 11,480 0.0320 1.74 Lag/CN Method, Existing Watershed Tc

Subcatchment 1S: Watershed Upstream of Culvert

Runoff

Hydrograph

Time (hours) 484644424038363432302826242220181614121086420

F lo w

(c fs

MSE 24-hr 4

10-Year Rainfall=4.43"

Runoff Area=899.170 ac

Runoff Volume=206.334 af

Runoff Depth=2.75"

Flow Length=11,480'

Slope=0.0320 '/'

Tc=109.9 min

CN=84

866.81 cfs

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Hydrograph for Subcatchment 1S: Watershed Upstream of Culvert

Time (hours)

Precip.

(inches)

Excess (inches)

Runoff (cfs)

0.00 0.00 0.00 0.00

0.50 0.01 0.00 0.00

1.00 0.02 0.00 0.00

1.50 0.04 0.00 0.00

2.00 0.05 0.00 0.00

2.50 0.07 0.00 0.00

3.00 0.09 0.00 0.00

3.50 0.12 0.00 0.00

4.00 0.14 0.00 0.00

4.50 0.17 0.00 0.00

5.00 0.20 0.00 0.00

5.50 0.24 0.00 0.00

6.00 0.27 0.00 0.00

6.50 0.31 0.00 0.00

7.00 0.35 0.00 0.00

7.50 0.39 0.00 0.00

8.00 0.44 0.00 0.05

8.50 0.49 0.01 0.55

9.00 0.54 0.01 2.10

9.50 0.62 0.03 4.93

10.00 0.70 0.05 9.98

10.50 0.79 0.07 18.03

11.00 0.96 0.13 28.65

11.50 1.20 0.25 47.80

12.00 2.08 0.80 92.52

12.50 3.23 1.71 273.52

13.00 3.47 1.91 683.98

13.50 3.64 2.05 866.80

14.00 3.73 2.13 714.92

14.50 3.81 2.21 479.79

15.00 3.89 2.28 326.72

15.50 3.94 2.32 232.44

16.00 3.99 2.36 173.87

16.50 4.04 2.40 132.63

17.00 4.08 2.44 105.01

17.50 4.12 2.48 88.76

18.00 4.16 2.51 77.93

18.50 4.19 2.54 70.47

19.00 4.23 2.57 65.47

19.50 4.26 2.60 61.19

20.00 4.29 2.62 57.24

20.50 4.31 2.65 53.39

21.00 4.34 2.67 49.59

21.50 4.36 2.69 45.83

22.00 4.38 2.71 42.06

22.50 4.39 2.72 38.28

23.00 4.41 2.73 34.49

23.50 4.42 2.74 30.69

24.00 4.43 2.75 26.88

24.50 4.43 2.75 22.80

25.00 4.43 2.75 17.11

25.50 4.43 2.75 10.44

Time (hours)

Precip.

(inches)

Excess (inches)

Runoff (cfs)

26.00 4.43 2.75 5.43

26.50 4.43 2.75 2.75

27.00 4.43 2.75 1.39

27.50 4.43 2.75 0.69

28.00 4.43 2.75 0.34

28.50 4.43 2.75 0.16

29.00 4.43 2.75 0.07

29.50 4.43 2.75 0.02

30.00 4.43 2.75 0.00

30.50 4.43 2.75 0.00

31.00 4.43 2.75 0.00

31.50 4.43 2.75 0.00

32.00 4.43 2.75 0.00

32.50 4.43 2.75 0.00

33.00 4.43 2.75 0.00

33.50 4.43 2.75 0.00

34.00 4.43 2.75 0.00

34.50 4.43 2.75 0.00

35.00 4.43 2.75 0.00

35.50 4.43 2.75 0.00

36.00 4.43 2.75 0.00

36.50 4.43 2.75 0.00

37.00 4.43 2.75 0.00

37.50 4.43 2.75 0.00

38.00 4.43 2.75 0.00

38.50 4.43 2.75 0.00

39.00 4.43 2.75 0.00

39.50 4.43 2.75 0.00

40.00 4.43 2.75 0.00

40.50 4.43 2.75 0.00

41.00 4.43 2.75 0.00

41.50 4.43 2.75 0.00

42.00 4.43 2.75 0.00

42.50 4.43 2.75 0.00

43.00 4.43 2.75 0.00

43.50 4.43 2.75 0.00

44.00 4.43 2.75 0.00

44.50 4.43 2.75 0.00

45.00 4.43 2.75 0.00

45.50 4.43 2.75 0.00

46.00 4.43 2.75 0.00

46.50 4.43 2.75 0.00

47.00 4.43 2.75 0.00

47.50 4.43 2.75 0.00

48.00 4.43 2.75 0.00

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Summary for Subcatchment 3S: Watershed Downstream of Culvert

Runoff = 816.20 cfs @ 13.01 hrs, Volume= 150.988 af, Depth= 2.75" Routed to Pond 4P : Existing Wetland Condition

Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-48.00 hrs, dt= 0.05 hrs MSE 24-hr 4 10-Year Rainfall=4.43"

Area (ac) CN Description

* 657.980 84 Weighted Average

657.980 100.00% Pervious Area

Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs)

76.4 7,292 0.0320 1.59 Lag/CN Method, Subcatchment 3S: Watershed Downstream of Culvert

Runoff

Hydrograph

Time (hours) 484644424038363432302826242220181614121086420

F

MSE 24-hr 4

10-Year Rainfall=4.43"

Runoff Area=657.980 ac

Runoff Volume=150.988 af

Runoff Depth=2.75"

Flow Length=7,292'

Slope=0.0320 '/'

Tc=76.4 min

816.20 cfs

Page 13HydroCAD® 10.20-2g s/n 04207 © 2022 HydroCAD Software Solutions LLC

Hydrograph for Subcatchment 3S: Watershed Downstream of Culvert

Time (hours)

Precip.

(inches)

Excess (inches)

Runoff (cfs)

0.00 0.00 0.00 0.00

0.50 0.01 0.00 0.00

1.00 0.02 0.00 0.00

1.50 0.04 0.00 0.00

2.00 0.05 0.00 0.00

2.50 0.07 0.00 0.00

3.00 0.09 0.00 0.00

3.50 0.12 0.00 0.00

4.00 0.14 0.00 0.00

4.50 0.17 0.00 0.00

5.00 0.20 0.00 0.00

5.50 0.24 0.00 0.00

6.00 0.27 0.00 0.00

6.50 0.31 0.00 0.00

7.00 0.35 0.00 0.00

7.50 0.39 0.00 0.00

8.00 0.44 0.00 0.12

8.50 0.49 0.01 1.06

9.00 0.54 0.01 3.08

9.50 0.62 0.03 6.13

10.00 0.70 0.05 12.10

10.50 0.79 0.07 20.02

11.00 0.96 0.13 29.90

11.50 1.20 0.25 54.58

12.00 2.08 0.80 113.39

12.50 3.23 1.71 434.38

13.00 3.47 1.91 815.81

13.50 3.64 2.05 603.51

14.00 3.73 2.13 358.91

14.50 3.81 2.21 217.86

15.00 3.89 2.28 145.58

15.50 3.94 2.32 112.03

16.00 3.99 2.36 85.59

16.50 4.04 2.40 66.60

17.00 4.08 2.44 58.25

17.50 4.12 2.48 53.52

18.00 4.16 2.51 50.14

18.50 4.19 2.54 47.19

19.00 4.23 2.57 44.40

19.50 4.26 2.60 41.67

20.00 4.29 2.62 38.95

20.50 4.31 2.65 36.22

21.00 4.34 2.67 33.48

21.50 4.36 2.69 30.72

22.00 4.38 2.71 27.95

22.50 4.39 2.72 25.17

23.00 4.41 2.73 22.38

23.50 4.42 2.74 19.58

24.00 4.43 2.75 16.78

24.50 4.43 2.75 13.35

25.00 4.43 2.75 7.46

25.50 4.43 2.75 2.93

Time (hours)

Precip.

(inches)

Excess (inches)

Runoff (cfs)

26.00 4.43 2.75 1.10

26.50 4.43 2.75 0.41

27.00 4.43 2.75 0.14

27.50 4.43 2.75 0.04

28.00 4.43 2.75 0.01

28.50 4.43 2.75 0.00

29.00 4.43 2.75 0.00

29.50 4.43 2.75 0.00

30.00 4.43 2.75 0.00

30.50 4.43 2.75 0.00

31.00 4.43 2.75 0.00

31.50 4.43 2.75 0.00

32.00 4.43 2.75 0.00

32.50 4.43 2.75 0.00

33.00 4.43 2.75 0.00

33.50 4.43 2.75 0.00

34.00 4.43 2.75 0.00

34.50 4.43 2.75 0.00

35.00 4.43 2.75 0.00

35.50 4.43 2.75 0.00

36.00 4.43 2.75 0.00

36.50 4.43 2.75 0.00

37.00 4.43 2.75 0.00

37.50 4.43 2.75 0.00

38.00 4.43 2.75 0.00

38.50 4.43 2.75 0.00

39.00 4.43 2.75 0.00

39.50 4.43 2.75 0.00

40.00 4.43 2.75 0.00

40.50 4.43 2.75 0.00

41.00 4.43 2.75 0.00

41.50 4.43 2.75 0.00

42.00 4.43 2.75 0.00

42.50 4.43 2.75 0.00

43.00 4.43 2.75 0.00

43.50 4.43 2.75 0.00

44.00 4.43 2.75 0.00

44.50 4.43 2.75 0.00

45.00 4.43 2.75 0.00

45.50 4.43 2.75 0.00

46.00 4.43 2.75 0.00

46.50 4.43 2.75 0.00

47.00 4.43 2.75 0.00

47.50 4.43 2.75 0.00

48.00 4.43 2.75 0.00

Page 14HydroCAD® 10.20-2g s/n 04207 © 2022 HydroCAD Software Solutions LLC

Summary for Pond 2P: 560th Ave Culvert

Inflow Area = 899.170 ac, 0.00% Impervious, Inflow Depth = 2.75" for 10-Year event Inflow = 866.81 cfs @ 13.49 hrs, Volume= 206.334 af Outflow = 855.07 cfs @ 13.61 hrs, Volume= 206.334 af, Atten= 1%, Lag= 7.3 min Primary = 397.66 cfs @ 13.61 hrs, Volume= 158.433 af Routed to Pond 4P : Existing Wetland Condition Secondary = 457.42 cfs @ 13.61 hrs, Volume= 47.901 af Routed to Pond 4P : Existing Wetland Condition

Routing by Dyn-Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.05 hrs Peak Elev= 1,235.54' @ 13.61 hrs Surf.Area= 10.572 ac Storage= 5.743 af

Plug-Flow detention time= 2.7 min calculated for 206.119 af (100% of inflow) Center-of-Mass det. time= 2.7 min ( 903.5 - 900.8 )

Volume Invert Avail.Storage Storage Description

#1 1,226.00' 66.349 af Custom Stage Data from Lidar (Prismatic) Listed below (Recalc)

Elevation Surf.Area Inc.Store Cum.Store (feet) (acres) (acre-feet) (acre-feet)

1,226.00 0.001 0.000 0.000 1,227.00 0.002 0.002 0.002 1,228.00 0.003 0.003 0.004 1,229.00 0.006 0.005 0.008 1,230.00 0.016 0.011 0.020 1,231.00 0.038 0.027 0.046 1,232.00 0.082 0.060 0.106 1,233.00 0.422 0.252 0.358 1,234.00 0.999 0.710 1.069 1,235.00 1.702 1.350 2.419 1,236.00 18.079 9.890 12.310 1,237.00 25.000 21.539 33.849 1,238.00 40.000 32.500 66.349

Device Routing Invert Outlet Devices

#1 Primary 1,226.36' 72.0" W x 60.0" H Box Existing 5x6 Road Culvert L= 25.0' Box, 30-75° wingwalls, square crown, Ke= 0.400 Inlet / Outlet Invert= 1,226.36' / 1,226.36' S= 0.0000 '/' Cc= 0.900 n= 0.012 Concrete pipe, finished, Flow Area= 30.00 sf

#2 Secondary 1,234.37' Gravel Road - Asymmetrical Weir, C= 3.27 Offset (feet) -214.93 -167.93 -88.67 0.00 82.37 132.11 157.11 Elev. (feet) 1,237.00 1,236.27 1,235.04 1,234.37 1,235.06 1,236.20 1,237.00

Primary OutFlow Max=397.64 cfs @ 13.61 hrs HW=1,235.54' TW=1,205.18' (Dynamic Tailwater) 1=Existing 5x6 Road Culvert (Inlet Controls 397.64 cfs @ 13.25 fps)

Secondary OutFlow Max=457.08 cfs @ 13.61 hrs HW=1,235.54' TW=1,205.18' (Dynamic Tailwater) 2=Gravel Road - Asymmetrical Weir (Weir Controls 457.08 cfs @ 2.02 fps)

Page 15HydroCAD® 10.20-2g s/n 04207 © 2022 HydroCAD Software Solutions LLC

Pond 2P: 560th Ave Culvert

Inflow Outflow Primary Secondary

Hydrograph

Time (hours) 484644424038363432302826242220181614121086420

F

Inflow Area=899.170 ac

Peak Elev=1,235.54'

Storage=5.743 af

866.81 cfs

855.07 cfs

397.66 cfs

457.42 cfs

Pond 2P: 560th Ave Culvert

Total Primary Secondary

Stage-Discharge

Discharge (cfs) 4,5004,0003,5003,0002,5002,0001,5001,0005000

E le v a ti o n

(f e e t)

1,238

1,237

1,236

1,235

1,234

1,233

1,232

1,231

1,230

1,229

1,228

1,227

1,226

Existing 5x6 Road Culvert

Gravel Road - Asymmetrical Weir

Page 16HydroCAD® 10.20-2g s/n 04207 © 2022 HydroCAD Software Solutions LLC

Pond 2P: 560th Ave Culvert

Surface Storage

Stage-Area-Storage

Storage (acre-feet) 65605550454035302520151050

Surface/Horizontal/Wetted Area (acres) 403938373635343332313029282726252423222120191817161514131211109876543210

E le v a ti e t)

1,238

1,237

1,236

1,235

1,234

1,233

1,232

1,231

1,230

1,229

1,228

1,227

1,226 Custom Stage Data from Lidar

Page 17HydroCAD® 10.20-2g s/n 04207 © 2022 HydroCAD Software Solutions LLC

Hydrograph for Pond 2P: 560th Ave Culvert

Time (hours)

Inflow (cfs)

Storage (acre-feet)

Elevation (feet)

Outflow (cfs)

Primary (cfs)

Secondary (cfs)

0.00 0.00 0.000 1,226.00 0.00 0.00 0.00

1.00 0.00 0.000 1,226.00 0.00 0.00 0.00

2.00 0.00 0.000 1,226.00 0.00 0.00 0.00

3.00 0.00 0.000 1,226.00 0.00 0.00 0.00

4.00 0.00 0.000 1,226.00 0.00 0.00 0.00

5.00 0.00 0.000 1,226.00 0.00 0.00 0.00

6.00 0.00 0.000 1,226.00 0.00 0.00 0.00

7.00 0.00 0.000 1,226.00 0.00 0.00 0.00

8.00 0.05 0.000 1,226.39 0.02 0.02 0.00

9.00 2.10 0.001 1,226.67 2.10 2.10 0.00

10.00 9.98 0.002 1,227.16 9.97 9.97 0.00

11.00 28.65 0.004 1,227.93 28.62 28.62 0.00

12.00 92.52 0.015 1,229.72 91.86 91.86 0.00

13.00 683.98 3.256 1,235.23 612.64 388.10 224.55

14.00 714.92 4.770 1,235.44 768.22 394.60 373.62

15.00 326.72 1.667 1,234.51 354.68 352.35 2.33

16.00 173.87 0.072 1,231.51 175.29 175.29 0.00

17.00 105.01 0.020 1,230.04 105.21 105.21 0.00

18.00 77.93 0.011 1,229.38 77.99 77.99 0.00

19.00 65.47 0.009 1,229.05 65.50 65.50 0.00

20.00 57.24 0.007 1,228.82 57.25 57.25 0.00

21.00 49.59 0.006 1,228.60 49.61 49.61 0.00

22.00 42.06 0.005 1,228.37 42.07 42.07 0.00

23.00 34.49 0.004 1,228.13 34.50 34.50 0.00

24.00 26.88 0.004 1,227.87 26.89 26.89 0.00

25.00 17.11 0.003 1,227.49 17.12 17.12 0.00

26.00 5.43 0.001 1,226.91 5.44 5.44 0.00

27.00 1.39 0.001 1,226.61 1.40 1.40 0.00

28.00 0.34 0.001 1,226.47 0.34 0.34 0.00

29.00 0.07 0.000 1,226.41 0.07 0.07 0.00

30.00 0.00 0.000 1,226.37 0.00 0.00 0.00

31.00 0.00 0.000 1,226.36 0.00 0.00 0.00

32.00 0.00 0.000 1,226.36 0.00 0.00 0.00

33.00 0.00 0.000 1,226.36 0.00 0.00 0.00

34.00 0.00 0.000 1,226.36 0.00 0.00 0.00

35.00 0.00 0.000 1,226.36 0.00 0.00 0.00

36.00 0.00 0.000 1,226.36 0.00 0.00 0.00

37.00 0.00 0.000 1,226.36 0.00 0.00 0.00

38.00 0.00 0.000 1,226.36 0.00 0.00 0.00

39.00 0.00 0.000 1,226.36 0.00 0.00 0.00

40.00 0.00 0.000 1,226.36 0.00 0.00 0.00

41.00 0.00 0.000 1,226.36 0.00 0.00 0.00

42.00 0.00 0.000 1,226.36 0.00 0.00 0.00

43.00 0.00 0.000 1,226.36 0.00 0.00 0.00

44.00 0.00 0.000 1,226.36 0.00 0.00 0.00

45.00 0.00 0.000 1,226.36 0.00 0.00 0.00

46.00 0.00 0.000 1,226.36 0.00 0.00 0.00

47.00 0.00 0.000 1,226.36 0.00 0.00 0.00

48.00 0.00 0.000 1,226.36 0.00 0.00 0.00

Page 18HydroCAD® 10.20-2g s/n 04207 © 2022 HydroCAD Software Solutions LLC

Stage-Discharge for Pond 2P: 560th Ave Culvert

Elevation (feet)

Discharge (cfs)

Primary (cfs)

Secondary (cfs)

1,226.00 0.00 0.00 0.00 1,226.20 0.00 0.00 0.00 1,226.40 0.04 0.04 0.00 1,226.60 1.34 1.34 0.00 1,226.80 3.79 3.79 0.00 1,227.00 7.01 7.01 0.00 1,227.20 10.82 10.82 0.00 1,227.40 15.14 15.14 0.00 1,227.60 19.92 19.92 0.00 1,227.80 25.12 25.12 0.00 1,228.00 30.69 30.69 0.00 1,228.20 36.63 36.63 0.00 1,228.40 42.91 42.91 0.00 1,228.60 49.50 49.50 0.00 1,228.80 56.40 56.40 0.00 1,229.00 63.59 63.59 0.00 1,229.20 71.07 71.07 0.00 1,229.40 78.81 78.81 0.00 1,229.60 86.82 86.82 0.00 1,229.80 95.08 95.08 0.00 1,230.00 103.58 103.58 0.00 1,230.20 112.33 112.33 0.00 1,230.40 121.30 121.30 0.00 1,230.60 130.51 130.51 0.00 1,230.80 139.93 139.93 0.00 1,231.00 149.57 149.57 0.00 1,231.20 159.42 159.42 0.00 1,231.40 169.48 169.48 0.00 1,231.60 179.74 179.74 0.00 1,231.80 190.20 190.20 0.00 1,232.00 200.86 200.86 0.00 1,232.20 211.71 211.71 0.00 1,232.40 222.74 222.74 0.00 1,232.60 233.96 233.96 0.00 1,232.80 245.36 245.36 0.00 1,233.00 256.95 256.95 0.00 1,233.20 269.38 269.38 0.00 1,233.40 283.64 283.64 0.00 1,233.60 297.22 297.22 0.00 1,233.80 310.20 310.20 0.00 1,234.00 322.67 322.67 0.00 1,234.20 334.66 334.66 0.00 1,234.40 346.30 346.25 0.05 1,234.60 365.81 357.46 8.35 1,234.80 408.24 368.32 39.92 1,235.00 482.60 378.88 103.72 1,235.20 592.10 387.09 205.01 1,235.40 734.23 393.31 340.92 1,235.60 909.80 399.43 510.37 1,235.80 1,119.19 405.46 713.74 1,236.00 1,363.16 411.39 951.77 1,236.20 1,642.64 417.23 1,225.41

Elevation (feet)

Discharge (cfs)

Primary (cfs)

Secondary (cfs)

1,236.40 1,958.33 422.99 1,535.35 1,236.60 2,310.52 428.67 1,881.85 1,236.80 2,699.76 434.27 2,265.49 1,237.00 3,126.75 439.79 2,686.95 1,237.20 3,481.18 445.25 3,035.93 1,237.40 3,776.53 450.64 3,325.89 1,237.60 4,041.43 455.96 3,585.47 1,237.80 4,285.19 461.22 3,823.97 1,238.00 4,512.80 466.42 4,046.38

Page 19HydroCAD® 10.20-2g s/n 04207 © 2022 HydroCAD Software Solutions LLC

Stage-Area-Storage for Pond 2P: 560th Ave Culvert

Elevation (feet)

Surface (acres)

Storage (acre-feet)

1,226.00 0.001 0.000 1,226.20 0.001 0.000 1,226.40 0.001 0.000 1,226.60 0.002 0.001 1,226.80 0.002 0.001 1,227.00 0.002 0.002 1,227.20 0.002 0.002 1,227.40 0.002 0.002 1,227.60 0.003 0.003 1,227.80 0.003 0.003 1,228.00 0.003 0.004 1,228.20 0.004 0.005 1,228.40 0.004 0.005 1,228.60 0.005 0.006 1,228.80 0.005 0.007 1,229.00 0.006 0.008 1,229.20 0.008 0.010 1,229.40 0.010 0.012 1,229.60 0.012 0.014 1,229.80 0.014 0.016 1,230.00 0.016 0.020 1,230.20 0.020 0.023 1,230.40 0.025 0.028 1,230.60 0.029 0.033 1,230.80 0.034 0.039 1,231.00 0.038 0.046 1,231.20 0.047 0.055 1,231.40 0.056 0.065 1,231.60 0.064 0.077 1,231.80 0.073 0.091 1,232.00 0.082 0.106 1,232.20 0.150 0.130 1,232.40 0.218 0.167 1,232.60 0.286 0.217 1,232.80 0.354 0.281 1,233.00 0.422 0.358 1,233.20 0.537 0.454 1,233.40 0.653 0.573 1,233.60 0.768 0.716 1,233.80 0.884 0.881 1,234.00 0.999 1.069 1,234.20 1.140 1.283 1,234.40 1.280 1.525 1,234.60 1.421 1.795 1,234.80 1.561 2.093 1,235.00 1.702 2.419 1,235.20 4.977 3.087 1,235.40 8.253 4.410 1,235.60 11.528 6.389 1,235.80 14.804 9.022 1,236.00 18.079 12.310 1,236.20 19.463 16.064

Elevation (feet)

Surface (acres)

Storage (acre-feet)

1,236.40 20.847 20.095 1,236.60 22.232 24.403 1,236.80 23.616 28.988 1,237.00 25.000 33.849 1,237.20 28.000 39.150 1,237.40 31.000 45.050 1,237.60 34.000 51.549 1,237.80 37.000 58.649 1,238.00 40.000 66.349

Page 20HydroCAD® 10.20-2g s/n 04207 © 2022 HydroCAD Software Solutions LLC

Summary for Pond 4P: Existing Wetland Condition

Inflow Area = 1,557.150 ac, 0.00% Impervious, Inflow Depth = 2.75" for 10-Year event Inflow = 1,520.50 cfs @ 13.26 hrs, Volume= 357.322 af Outflow = 1,411.67 cfs @ 13.57 hrs, Volume= 357.297 af, Atten= 7%, Lag= 19.1 min Primary = 1,411.67 cfs @ 13.57 hrs, Volume= 357.297 af

Routing by Dyn-Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.05 hrs Peak Elev= 1,205.18' @ 13.57 hrs Surf.Area= 14.144 ac Storage= 45.707 af

Plug-Flow detention time= 33.2 min calculated for 356.925 af (100% of inflow) Center-of-Mass det. time= 33.4 min ( 922.5 - 889.1 )

Volume Invert Avail.Storage Storage Description

#1 1,199.00' 94.165 af Custom Stage Data (Prismatic) Listed below (Recalc)

Elevation Surf.Area Inc.Store Cum.Store (feet) (acres) (acre-feet) (acre-feet)

1,199.00 0.002 0.000 0.000 1,200.00 1.684 0.843 0.843 1,201.00 6.154 3.919 4.762 1,202.00 7.956 7.055 11.817 1,203.00 9.499 8.728 20.544 1,204.00 11.030 10.264 30.809 1,205.00 13.737 12.383 43.192 1,206.00 15.991 14.864 58.057 1,207.00 18.042 17.016 75.073 1,208.00 20.142 19.092 94.165

Device Routing Invert Outlet Devices

#1 Primary 1,199.12' Existing Outlet Channel to Lake, C= 3.27 Offset (feet) -106.52 -44.01 -15.95 0.00 10.33 70.05 Elev. (feet) 1,213.23 1,204.05 1,201.65 1,199.12 1,201.69 1,213.23

Primary OutFlow Max=1,411.01 cfs @ 13.57 hrs HW=1,205.18' (Free Discharge) 1=Existing Outlet Channel to Lake (Weir Controls 1,411.01 cfs @ 4.28 fps)

Page 21HydroCAD® 10.20-2g s/n 04207 © 2022 HydroCAD Software Solutions LLC

Pond 4P: Existing Wetland Condition

Inflow Primary

Hydrograph

Time (hours) 484644424038363432302826242220181614121086420

F

1,700

1,600

1,500

1,400

1,300

1,200

1,100

1,000

Inflow Area=1,557.150 ac

Peak Elev=1,205.18'

Storage=45.707 af

1,520.50 cfs

1,411.67 cfs

Pond 4P: Existing Wetland Condition

Primary

Stage-Discharge

Discharge (cfs) 12,00010,0008,0006,0004,0002,0000

E le v a ti e t)

1,213

1,212

1,211

1,210

1,209

1,208

1,207

1,206

1,205

1,204

1,203

1,202

1,201

1,200

1,199

Existing Outlet Channel to Lake

Page 22HydroCAD® 10.20-2g s/n 04207 © 2022 HydroCAD Software Solutions LLC

Pond 4P: Existing Wetland Condition

Surface Storage

Stage-Area-Storage

Storage (acre-feet) 9080706050403020100

Surface/Horizontal/Wetted Area (acres) 20181614121086420

E le v a ti e t)

1,213

1,212

1,211

1,210

1,209

1,208

1,207

1,206

1,205

1,204

1,203

1,202

1,201

1,200

Custom Stage Data

Page 23HydroCAD® 10.20-2g s/n 04207 © 2022 HydroCAD Software Solutions LLC

Hydrograph for Pond 4P: Existing Wetland Condition

Time (hours)

Inflow (cfs)

Storage (acre-feet)

Elevation (feet)

Primary (cfs)

0.00 0.00 0.000 1,199.00 0.00

1.00 0.00 0.000 1,199.00 0.00

2.00 0.00 0.000 1,199.00 0.00

3.00 0.00 0.000 1,199.00 0.00

4.00 0.00 0.000 1,199.00 0.00

5.00 0.00 0.000 1,199.00 0.00

6.00 0.00 0.000 1,199.00 0.00

7.00 0.00 0.000 1,199.00 0.00

8.00 0.14 0.001 1,199.04 0.00

9.00 5.18 0.154 1,199.43 0.70

10.00 22.06 0.819 1,199.99 9.41

11.00 58.51 2.382 1,200.53 32.14

12.00 205.25 6.898 1,201.33 98.16

13.00 1,428.45 35.616 1,204.41 978.64

14.00 1,127.12 42.650 1,204.96 1,277.79

15.00 500.26 27.170 1,203.66 642.49

16.00 260.88 18.135 1,202.74 347.37

17.00 163.45 12.723 1,202.11 210.41

18.00 128.13 9.922 1,201.75 152.22

19.00 109.90 8.398 1,201.55 123.92

20.00 96.20 7.414 1,201.41 106.78

21.00 83.08 6.580 1,201.28 92.99

22.00 70.03 5.759 1,201.16 80.11

23.00 56.88 4.906 1,201.02 67.49

24.00 43.66 4.005 1,200.87 54.78

25.00 24.58 2.966 1,200.67 40.27

26.00 6.54 1.603 1,200.32 21.19

27.00 1.54 0.736 1,199.93 8.08

28.00 0.35 0.381 1,199.67 3.06

29.00 0.07 0.225 1,199.52 1.34

30.00 0.00 0.149 1,199.42 0.66

31.00 0.00 0.108 1,199.36 0.37

32.00 0.00 0.084 1,199.31 0.23

33.00 0.00 0.069 1,199.28 0.15

34.00 0.00 0.058 1,199.26 0.10

35.00 0.00 0.051 1,199.25 0.08

36.00 0.00 0.046 1,199.23 0.06

37.00 0.00 0.042 1,199.22 0.04

38.00 0.00 0.038 1,199.21 0.04

39.00 0.00 0.036 1,199.21 0.03

40.00 0.00 0.034 1,199.20 0.02

41.00 0.00 0.032 1,199.19 0.02

42.00 0.00 0.030 1,199.19 0.02

43.00 0.00 0.029 1,199.18 0.01

44.00 0.00 0.028 1,199.18 0.01

45.00 0.00 0.027 1,199.18 0.01

46.00 0.00 0.026 1,199.18 0.01

47.00 0.00 0.025 1,199.17 0.01

48.00 0.00 0.025 1,199.17 0.01

Page 24HydroCAD® 10.20-2g s/n 04207 © 2022 HydroCAD Software Solutions LLC

Stage-Discharge for Pond 4P: Existing Wetland Condition

Elevation (feet)

Primary (cfs)

1,199.00 0.00 1,199.10 0.00 1,199.20 0.02 1,199.30 0.19 1,199.40 0.56 1,199.50 1.20 1,199.60 2.16 1,199.70 3.46 1,199.80 5.15 1,199.90 7.26 1,200.00 9.81 1,200.10 12.84 1,200.20 16.37 1,200.30 20.42 1,200.40 25.03 1,200.50 30.21 1,200.60 35.98 1,200.70 42.37 1,200.80 49.40 1,200.90 57.08 1,201.00 65.44 1,201.10 74.49 1,201.20 84.26 1,201.30 94.75 1,201.40 105.99 1,201.50 118.00 1,201.60 130.79 1,201.70 144.38 1,201.80 158.84 1,201.90 174.25 1,202.00 190.67 1,202.10 208.13 1,202.20 226.68 1,202.30 246.35 1,202.40 267.18 1,202.50 289.21 1,202.60 312.46 1,202.70 336.97 1,202.80 362.76 1,202.90 389.87 1,203.00 418.32 1,203.10 448.14 1,203.20 479.36 1,203.30 511.99 1,203.40 546.08 1,203.50 581.63 1,203.60 618.68 1,203.70 657.25 1,203.80 697.36 1,203.90 739.04 1,204.00 782.30 1,204.10 827.18

Elevation (feet)

Primary (cfs)

1,204.20 873.63 1,204.30 921.64 1,204.40 971.21 1,204.50 1,022.34 1,204.60 1,075.02 1,204.70 1,129.26 1,204.80 1,185.06 1,204.90 1,242.42 1,205.00 1,301.37 1,205.10 1,361.89 1,205.20 1,424.01 1,205.30 1,487.72 1,205.40 1,553.03 1,205.50 1,619.95 1,205.60 1,688.50 1,205.70 1,758.67 1,205.80 1,830.48 1,205.90 1,903.93 1,206.00 1,979.04 1,206.10 2,055.81 1,206.20 2,134.25 1,206.30 2,214.38 1,206.40 2,296.19 1,206.50 2,379.70 1,206.60 2,464.92 1,206.70 2,551.85 1,206.80 2,640.51 1,206.90 2,730.90 1,207.00 2,823.03 1,207.10 2,916.92 1,207.20 3,012.57 1,207.30 3,109.99 1,207.40 3,209.18 1,207.50 3,310.17 1,207.60 3,412.95 1,207.70 3,517.54 1,207.80 3,623.94 1,207.90 3,732.17 1,208.00 3,842.22 1,208.10 3,954.12 1,208.20 4,067.87 1,208.30 4,183.48 1,208.40 4,300.96 1,208.50 4,420.31 1,208.60 4,541.55 1,208.70 4,664.68 1,208.80 4,789.71 1,208.90 4,916.66 1,209.00 5,045.53 1,209.10 5,176.32 1,209.20 5,309.05 1,209.30 5,443.73

Elevation (feet)

Primary (cfs)

1,209.40 5,580.36 1,209.50 5,718.95 1,209.60 5,859.52 1,209.70 6,002.06 1,209.80 6,146.60 1,209.90 6,293.12 1,210.00 6,441.66 1,210.10 6,592.21 1,210.20 6,744.77 1,210.30 6,899.37 1,210.40 7,056.01 1,210.50 7,214.69 1,210.60 7,375.43 1,210.70 7,538.23 1,210.80 7,703.10 1,210.90 7,870.05 1,211.00 8,039.08 1,211.10 8,210.21 1,211.20 8,383.45 1,211.30 8,558.79 1,211.40 8,736.25 1,211.50 8,915.85 1,211.60 9,097.57 1,211.70 9,281.44 1,211.80 9,467.46 1,211.90 9,655.64 1,212.00 9,845.98 1,212.10 10,038.50 1,212.20 10,233.20 1,212.30 10,430.09 1,212.40 10,629.18 1,212.50 10,830.47 1,212.60 11,033.98 1,212.70 11,239.71 1,212.80 11,447.66 1,212.90 11,657.85 1,213.00 11,870.29 1,213.10 12,084.97 1,213.20 12,301.92

Page 25HydroCAD® 10.20-2g s/n 04207 © 2022 HydroCAD Software Solutions LLC

Stage-Area-Storage for Pond 4P: Existing Wetland Condition

Elevation (feet)

Surface (acres)

Storage (acre-feet)

1,199.00 0.002 0.000 1,199.20 0.338 0.034 1,199.40 0.675 0.135 1,199.60 1.011 0.304 1,199.80 1.348 0.540 1,200.00 1.684 0.843 1,200.20 2.578 1.269 1,200.40 3.472 1.874 1,200.60 4.366 2.658 1,200.80 5.260 3.621 1,201.00 6.154 4.762 1,201.20 6.514 6.029 1,201.40 6.875 7.368 1,201.60 7.235 8.779 1,201.80 7.596 10.262 1,202.00 7.956 11.817 1,202.20 8.265 13.439 1,202.40 8.573 15.123 1,202.60 8.882 16.868 1,202.80 9.190 18.676 1,203.00 9.499 20.544 1,203.20 9.805 22.475 1,203.40 10.111 24.467 1,203.60 10.418 26.519 1,203.80 10.724 28.634 1,204.00 11.030 30.809 1,204.20 11.571 33.069 1,204.40 12.113 35.438 1,204.60 12.654 37.914 1,204.80 13.196 40.499 1,205.00 13.737 43.192 1,205.20 14.188 45.985 1,205.40 14.639 48.868 1,205.60 15.089 51.840 1,205.80 15.540 54.903 1,206.00 15.991 58.057 1,206.20 16.401 61.296 1,206.40 16.811 64.617 1,206.60 17.222 68.020 1,206.80 17.632 71.506 1,207.00 18.042 75.073 1,207.20 18.462 78.723 1,207.40 18.882 82.458 1,207.60 19.302 86.276 1,207.80 19.722 90.179 1,208.00 20.142 94.165 1,208.20 20.142 94.165 1,208.40 20.142 94.165 1,208.60 20.142 94.165 1,208.80 20.142 94.165 1,209.00 20.142 94.165 1,209.20 20.142 94.165

Elevation (feet)

Surface (acres)

Storage (acre-feet)

1,209.40 20.142 94.165 1,209.60 20.142 94.165 1,209.80 20.142 94.165 1,210.00 20.142 94.165 1,210.20 20.142 94.165 1,210.40 20.142 94.165 1,210.60 20.142 94.165 1,210.80 20.142 94.165 1,211.00 20.142 94.165 1,211.20 20.142 94.165 1,211.40 20.142 94.165 1,211.60 20.142 94.165 1,211.80 20.142 94.165 1,212.00 20.142 94.165 1,212.20 20.142 94.165 1,212.40 20.142 94.165 1,212.60 20.142 94.165 1,212.80 20.142 94.165 1,213.00 20.142 94.165 1,213.20 20.142 94.165

MSE 24-hr 4 25-Year Rainfall=5.57"IA-340-13 - Neary - Existing Condition - Simplified Furt

Page 26HydroCAD® 10.20-2g s/n 04207 © 2022 HydroCAD Software Solutions LLC

Time span=0.00-48.00 hrs, dt=0.05 hrs, 961 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN

Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method

Runoff Area=899.170 ac 0.00% Impervious Runoff Depth=3.80"Subcatchment 1S: Watershed Upstream Flow Length=11,480' Slope=0.0320 '/' Tc=109.9 min CN=84 Runoff=1,192.77 cfs 284.418 af

Runoff Area=657.980 ac 0.00% Impervious Runoff Depth=3.80"Subcatchment 3S: Watershed Flow Length=7,292' Slope=0.0320 '/' Tc=76.4 min CN=84 Runoff=1,122.05 cfs 208.126 af

Peak Elev=1,235.84' Storage=9.693 af Inflow=1,192.77 cfs 284.418 afPond 2P: 560th Ave Culvert Primary=406.78 cfs 191.067 af Secondary=763.36 cfs 93.350 af Outflow=1,170.14 cfs 284.417 af

Peak Elev=1,205.96' Storage=57.348 af Inflow=2,070.29 cfs 492.544 afPond 4P: Existing Wetland Outflow=1,945.44 cfs 492.519 af

Total Runoff Area = 1,557.150 ac Runoff Volume = 492.544 af Average Runoff Depth = 3.80"

Page 27HydroCAD® 10.20-2g s/n 04207 © 2022 HydroCAD Software Solutions LLC

Summary for Subcatchment 1S: Watershed Upstream of Culvert

Runoff = 1,192.77 cfs @ 13.46 hrs, Volume= 284.418 af, Depth= 3.80" Routed to Pond 2P : 560th Ave Culvert

Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-48.00 hrs, dt= 0.05 hrs MSE 24-hr 4 25-Year Rainfall=5.57"

Area (ac) CN Description

* 899.170 84 Weighted Average

899.170 100.00% Pervious Area

Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs)

109.9 11,480 0.0320 1.74 Lag/CN Method, Existing Watershed Tc

Subcatchment 1S: Watershed Upstream of Culvert

Runoff

Hydrograph

Time (hours) 484644424038363432302826242220181614121086420

F

1,300

1,200

1,100

1,000

MSE 24-hr 4

25-Year Rainfall=5.57"

Runoff Area=899.170 ac

Runoff Volume=284.418 af

Runoff Depth=3.80"

Flow Length=11,480'

Slope=0.0320 '/'

Tc=109.9 min

1,192.77 cfs

Page 28HydroCAD® 10.20-2g s/n 04207 © 2022 HydroCAD Software Solutions LLC

Hydrograph for Subcatchment 1S: Watershed Upstream of Culvert

Time (hours)

Precip.

(inches)

Excess (inches)

Runoff (cfs)

0.00 0.00 0.00 0.00

0.50 0.01 0.00 0.00

1.00 0.03 0.00 0.00

1.50 0.05 0.00 0.00

2.00 0.07 0.00 0.00

2.50 0.09 0.00 0.00

3.00 0.12 0.00 0.00

3.50 0.15 0.00 0.00

4.00 0.18 0.00 0.00

4.50 0.22 0.00 0.00

5.00 0.26 0.00 0.00

5.50 0.30…