Erickson Consulting Engineers, Inc. Karyn Erickson, ME, PE, D CE, Project Director Christin Perkinson, PhD, PE, D CE, Project Manager Sarasota County’s Siesta Beach Stormwater Outfall Project “Constructed” In Preparation for the Naples Beach Restoration & Water Quality Improvement Project 30% Design April 18, 2016
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Erickson Consulting Engineers, Inc. Karyn Erickson, ME, PE, D CE, Project Director
Christin Perkinson, PhD, PE, D CE, Project Manager
Sarasota County’s Siesta Beach Stormwater Outfall Project
“Constructed”
In Preparation for the Naples Beach Restoration & Water Quality Improvement Project 30% Design
April 18, 2016
Presentation Overview Siesta Beach (Sarasota County) Stormwater System Project Need Site Conditions Project Goals and Objectives Design Requirements Alternatives Considered Final Design and Constructed Project
Naples Beach Stormwater Outfalls May 16, 2016 Council Workshop
Discussion
2
Siesta Beach: Project Need Existing Outfall Identified as Source of
Bacteria causing multiple Beach Closures
Blocked Discharge from Sand Buildup
Beach Road Flooding Due to Back-up of Existing Beach Outfall
Degrades Aesthetics and Impacts Tourism
3
Site Conditions – Siesta Beach
Beach Outfall
Location of Stormwater Pond
Channel
Beach Outfall
Siesta Beach Ranked #1 Best Beach in America (2012)
1. Improve lateral beach access by removing outfall
2. Reduce flooding and improve water quality
3. Reduce environmental impacts to beach & nearshore resources
4. Meet or exceed existing level of service:
2.5 Yr rain event (5 Yr - City of Naples Comprehensive Plan)
25 Yr rain event (SFWMD)
5. Convey stormwater to pump station, treatment & offshore discharge
6. Community education (project objectives & design components)
6
Goals & Objectives
Design Requirements Prevent Erosion to Beach - Dune System
Subsurface Pipeline to Offshore Discharge Overflow Capacity for Extreme Rainfall Events Water No Longer Stages to Flow to Gulf
Treat Discharge for SS and Bacteria Two Stage Treatment (Filtration and UV Disinfection)
Improve Function of Existing S/W System Pump Station to Increase System Efficiencies (pond
changes to increase attenuation) Low Relief Diffuser System to Minimize Impacts Scalability to Allow for Changes to Components Eliminate Impacts to Beach-Dune-Nearshore System
7
Approximate -18 ft Depth
of Closure
Siesta Beach Section View
9
(Pump Station to Offshore Diffusers)
Pump Station with Treatment and Discharge to Roberts Bay via Grand Canal (1.5 in rain event)
Pump Station with Treatment (1.5 in rain event) and Offshore Gulf Discharge
Pump Station with Treatment (SS and Bacteria), Upstream Pipeline Increased (2.5 in rain event), and Offshore Gulf Discharge Full Capacity for 1 ft sea level rise and 4 ft storm surge System Redundancy (2 Pumps – Duplex ) Overflow for Extreme Flood Events Water Quality Monitoring (evaluate and tune system)
10
Alternative Systems
Pipeline Diffuser System
11
Filtration & UV Treatment System
12
Final Design & Construction
Pipeline Material 16” HDPE Or FPVC
Pipeline Length 3,200 ft (from pump station) 3,090 ft (HDD placement)
Pipeline Placement Horizontal Directional Drill (HDD)
Filtration System Storm Filter by Contech (siphon actuated, media-filled cartridges)
Bacteria Treatment System UV Disinfection by Acquionics
Discharge Capacity 2.5 in Rainfall Event
HDD Pipeline Below Seabed 40 ft
Depth of Emergent Pipeline 18 ft
Anchoring System 12 Helical Anchors
Diffuser System Power Seal Tapping Sleeve Tideflex Duckbill Diffuser
13
14
Siesta Beach Construction
40 ft below seabed from Pump Station to Offshore (3,000 ft)
“Constructed” Siesta Beach Stormwater System
15
WQ Monitoring & System Performance
16
0
500
1000
1500
2000
2500
3000
3500
4000
Pipe Pond Pre-UV Post-UV
Fecal Coliform
Feca
l Col
iform
#co
l/100
mL
12/8/201412/22/20141/5/20151/20/20152/2/20152/20/20153/2/20153/20/20153/30/20154/13/20155/11/20155/26/20156/8/20156/22/20157/6/20157/20/20157/28/20158/4/20158/17/20159/1/20159/15/20159/28/201510/12/201510/26/201511/9/201511/24/201512/7/2015
400 Max.
400 Col/100mL Standard
Conclusions Stormwater Consolidation & Treatment with Discharge
Offshore is an Effective Solution
Removes Bacterial and Fine Sediments to Protect Nearshore Water Quality
Eliminates Erosion of Nourished Beaches Between Nourishments
Road Flooding Eliminated
17
City Council Workshop - May 16, 2016 Project Objectives Design Analysis and Requirements Beach and Environmental Conditions Consolidation Alternatives Cost Estimates Evaluation of Alternatives 30% Preliminary Design Report
18
City of Naples
Questions and Discussion
Related Documents
