Preparing Bostons Water and Sewer Systems for Future Design Storms - - PowerPoint PPT Presentation

preparing boston s water and sewer systems for future
SMART_READER_LITE
LIVE PREVIEW

Preparing Bostons Water and Sewer Systems for Future Design Storms - - PowerPoint PPT Presentation

Preparing Bostons Water and Sewer Systems for Future Design Storms John P Sullivan, P.E. Boston Water and Sewer Commission November 22, 2019 DISCUSSION TOPICS Present Condition & Upgrades to Existing Systems Improved Stormwater


slide-1
SLIDE 1

Preparing Boston’s Water and Sewer Systems for Future Design Storms

John P Sullivan, P.E. Boston Water and Sewer Commission November 22, 2019

slide-2
SLIDE 2

DISCUSSION TOPICS

 Present Condition & Upgrades to Existing Systems  Improved Stormwater and Inundation Modelling  Upland Control of Stormwater  Coastal Stormwater Discharge Analysis  Smart Sewers

slide-3
SLIDE 3
slide-4
SLIDE 4

STORMWATER WATERSHEDS

slide-5
SLIDE 5

TIDE GATES MOUNTED ON SEA WALL

slide-6
SLIDE 6

NEW TIDE GATES

  • MT. WASHINGTON AVE
slide-7
SLIDE 7

WHY ARE TIDE GATES IMPORTANT

slide-8
SLIDE 8

Boston Stormwater Management

 Total Maximum Daily Load (2007)

 Phosphorus: Upper & Middle/Lower Charles River

 Consent Decree (2012)

 Update Stormwater Model  Create BMP Implementation Plan  Implement 3 Pilot Green Infrastructure/Low Impact Development

(“GI/LID”) Projects Central Square, Audubon Circle, City Hall Plaza

slide-9
SLIDE 9
slide-10
SLIDE 10

GI/LID Obstacles in Boston

Commission does not own land for GI/LID

  • Need to work with other agencies and

entities

Department of Public Works

Department of Transportation

Boston Parks and Recreation Department

Boston Public Schools

Boston Planning and Development Agency

  • Need to work with private property owners
  • Need complete understanding of who is

responsible for continued maintenance

slide-11
SLIDE 11
slide-12
SLIDE 12

Year 2060 Rain Sea Level Rise, With Storm Surge

slide-13
SLIDE 13

Today’s Extreme High Tides

slide-14
SLIDE 14
slide-15
SLIDE 15

Source: CHI Water

Develop improved models to show extent and duration of inundation in major wet weather events

IMPROVED INUNDATION MODELLING

slide-16
SLIDE 16

2030 STORMS

GARR SEPTEMBER 9TH,1999, W/ 2030 SLR GARR JUNE 12TH,1998, W/ 2030 SLR GARR AUGUST 2ND, 2017, W/ 2030 SLR AIRMASS 2-YEAR W/ 2030 SLR AIRMASS 10-YEAR W/ 2030 SLR FRONTAL 10-YEAR W/ 2030 SLR TROPICAL 10-YEAR W/ 2030 SLR FRONTAL 50-YEAR W/ 2030 SLR NOR’EASTER 10-YEAR W/ 2030 SLR NOR’EASTER 50-YEAR W/ 2030 SLR NOR’EASTER 50-YEAR W/ 2030 SLR + 100-YEAR STORM SURGE TROPICAL 100-YEAR W/ 2030 SLR +100-YEAR STORM SURGE NOR’EASTER 100-YEAR W/ 2030 SLR + 100-YEAR STORM SURGE TROPICAL 500-YEAR W/ 2030 SLR + 500-YEAR STORM SURGE

2070 STORMS

GARR SEPTEMBER 9TH,1999, W/ 2070 SLR GARR JUNE 12TH,1998, W/ 2070 SLR GARR AUGUST 2ND, 2017 W/ 2070 SLR AIRMASS 2-YEAR W/ 2070 SLR AIRMASS 10-YEAR W/ 2070 SLR FRONTAL 10-YEAR W/ 2070 SLR TROPICAL 10-YEAR W/ 2070 SLR FRONTAL 50-YEAR W/ 2070 SLR NOR’EASTER 50-YEAR W/ 2070 SLR + 100-YEAR STORM SURGE NOR’EASTER 100-YEAR W/ 2070 SLR + 500-YEAR STORM SURGE TROPICAL 100-YEAR W/ 2070 SLR +100-YEAR STORM SURGE TROPICAL 500-YEAR W/ 2070 SLR + 500-YEAR STORM SURGE

GARR – Gauge-Adjusted Radar Rainfall Airmass – summer thunderstorm Frontal Storms – advancing warm or cold airmasses Tropical – Hurricanes Nor’easters – Nor’easters

slide-17
SLIDE 17

2 4 6 8 10 12 14 1948 1953 1958 1963 1968 1973 1978 1983 1988 1993 1998 2003 2008 2013

Rainfall, in Date

Twenty Largest Storms from 1948 to 2017

using Logan Airport and BWSC Rain Gages

rainfall

  • ld 10 yr storm

atlas 14 storm

Old 10 yr / 24 hr Design Storm = 4.86 in. Atlas 14 - 10 yr / 24 hr Design Storm = 5.15 in.

slide-18
SLIDE 18

NEW INUNDATION ANALYSIS

slide-19
SLIDE 19

IMPROVED ESTIMATES OF FUTURE FLOODING DEPTHS AND EXTENTS

slide-20
SLIDE 20

DETAILED FLOOD DEPTHS AVAILABLE FOR EXTREMELY SMALLER SUB-AREAS

slide-21
SLIDE 21

IMPROVED VISUALS FOR ENHANCED PUBLIC UNDERSTANDING

slide-22
SLIDE 22

STORMWATER DETENTION

IDENTIFY AREAS TO DETAIN STORMWATER DURING EXTREME EVENTS AND POSSIBLY PROVIDE TREATMENT DURING MINOR EVENTS

slide-23
SLIDE 23

TOP AREAS FOR POSSIBLE STORMWATER DETENTION

slide-24
SLIDE 24

STORMWATER DETENTION WITH PHOSPHOROUS TREATMENT CAPABILITIES

slide-25
SLIDE 25
slide-26
SLIDE 26
slide-27
SLIDE 27
slide-28
SLIDE 28

FORT POINT CHANNEL STORAGE

slide-29
SLIDE 29

Smart Sewers

slide-30
SLIDE 30

CONTINUING FORWARD

  • INVESTIGATE PIPES THAT NEED TIDE GATES
  • COORDINATE WITH CITY ON BARRIERS AND THE NEED FOR TIDE GATES TO ENSURE COMMISSION PIPES DO NOT ACT

AS BY-PASS TO BARRIER

  • INVESTIGATE CATCH BASINS THAT MAY DISCHARGE TO COMBINED SYSTEMS IN AREAS THAT MAY BE PRONE TO

INUNDATION

  • CONTINUE TO COORDINATE WITH CITY ON CLIMATE CHANGE STRATEGIES
  • INVESTIGATE AREAS TO STORE STORMWATER DURING LARGE EVENTS
  • CREATE INUNDATION MODEL TO IDENTIFY AREAS: THAT MAY NEED TO BE EVACUATED IN EXTREME EVENTS; DISRUPT

TRANSPORTATION; IMPACT POTENTIAL EVACUATION CENTERS; IMPACT HEALTH CARE FACILITIES

  • INSPECT TIDE GATES AND OUTFALLS
  • MONITOR RAIN DATA TO GATHER INFORMATION ON STORM EVENTS AND INTENSITY
  • CONDUCT MONITORING ON DORCHESTER INTERCEPTOR
  • IDENTIFY STRATEGIC MONITORING LOCATIONS AND INSTALL METERS TO GATHER INFORMATION ON HOW SYSTEM

RESPONDS TO CHANGING RAIN EVENTS