Virginia’s 1st Design-Build Water - PC Construction · 2012-04-27 · Virginia’s 1st...

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Hopewell Water Treatment Plant

Virginia’s 1st Design-Build Water Treatment Plant Retrofit Project

Dave Johnson – PC Construction Laurence Zimmermann – Gannett Fleming

Michael Youshock – VA American Water Ryan Ural – American Water

VAW is a subsidiary of American Water, the largest investor owned water/wastewater utility in the US.

Provides water service to approximately 57,000 customers

Operations in 4 districts in VA: Alexandria, Prince William, Warsaw & Hopewell.

VAW Hopewell - Overview

Alexandria

Prince William Warsaw

HOPEWELL

Richmond

VAW Hopewell Service to 9,300 customers,

incl several large industries & Fort Lee military base.

Treatment capacity: 36 MGD Plant produces potable and

non-potable (industrial) grades of water

Source water: Appomattox River

(tidal tributary of James River)

Hopewell Water System •Unique Aspects:

•Plant produces 2 grades of water, potable and non-potable (industrial). •Numerous facilities operating nearing 100 years of service. •Tidal source water, widely varying raw water quality characteristics. •6 Industrial customers use 80-85% of all water produced, wide swing in usage patterns. •Limited tolerance of service disruptions

•Need for WTP Improvements: •Industrial wood tub filters at end of useful life, difficult to repair. •Potable plant operating at 12 mgd firm capacity during peak months.

Plant produces 2 grades of water: potable (Domestic) & non-potable (Industrial) Numerous facilities operating, nearing 100 years of service. Tidal source water, widely varying raw water quality characteristics. 6 Industrial customers use 80-85% of all water produced. Wide swing in usage patterns & limited tolerance of service disruptions.

Hopewell Water System •Unique Aspects:

•Plant produces 2 grades of water, potable and non-potable (industrial). •Numerous facilities operating nearing 100 years of service. •Tidal source water, widely varying raw water quality characteristics. •6 Industrial customers use 80-85% of all water produced, wide swing in usage patterns. •Limited tolerance of service disruptions

•Need for WTP Improvements: •Industrial wood tub filters at end of useful life, difficult to repair. •Potable plant operating at 12 mgd firm capacity during peak months.

Need for Improvements

Industrial wood tub filters at end of useful life, difficult to repair. Potable plant operating at 12 MGD firm capacity during peak months. Need additional space for office staff & maintenance facility. Existing operator’s laboratory outdated and not efficient.

Hopewell Water System •Unique Aspects:

•Plant produces 2 grades of water, potable and non-potable (industrial). •Numerous facilities operating nearing 100 years of service. •Tidal source water, widely varying raw water quality characteristics. •6 Industrial customers use 80-85% of all water produced, wide swing in usage patterns. •Limited tolerance of service disruptions

•Need for WTP Improvements: •Industrial wood tub filters at end of useful life, difficult to repair. •Potable plant operating at 12 mgd firm capacity during peak months.

REPLACEMENTS & UPGRADES IN AN ACTIVE WATER PLANT VERY TIGHT BUDGET – LARGE SCOPE OF WORK OLD FACILITY (“This Old House” for Water Treatment Plants) PROJECT SCHEDULE & TIMING

Project Scope DOMESTIC SYSTEM

Increase potable system capacity to 15 MGD reliable (18 MGD total) Upgrade sedimentation basins & install tube settlers Add 2 new domestic filters & 4 new GAC vessels Add 2.5 MG clearwell Add/replace high service pumps Chemical feed improvements Administration & maintenance building additions Control & instrumentation improvements

INDUSTRIAL SYSTEM Demolition of Industrial Wood Tub Filters Replace existing wood tubs with 4 high rate multi-media filters Wastewater improvements

Repair sed basins & install tube settlers ADDED SCOPE: Increase emergency generator power

2 new domestic filters

4 new GAC vessels

New 2.5 MG clearwell

Add & replace high service pumps

Admin building addition

Chemical feed improvements

Demolish tub filters

4 new industrial filters

Demolish old lab, build new one

Project Scope – VAW Hopewell

Why Design-Build?

1. Minimize project timeframe: Existing facilities failing & needed expansion of plant capacity.

2. Active WTP: Complex tie-ins required to minimize impact on operations Detailed coordination required from design to start-up.

Design-Build would give the Owner flexibility to deal with the unique challenges of an aged facility, while keeping on schedule and budget.

Selection Process: RFQ sent to pre-qual list of engineers & contractors

VAW/AW evaluated interested D/B teams.

AW sent RFP to shortlisted teams.

VAW/AW received proposals: costs & fees in separate sealed envelope

Quals-based evaluation by Owner (with score card)

Cost & Fees opened & evaluated.

VAW/AW reached consensus on “best match” to project

Project Timeline June 2008 – American Water issues RFP July 2008 – Proposals received September 2008 – Notice of Award November 2008 – Notice to Proceed

May 2009 – 60% Target Cost: $16.2M July 2009 – Groundbreaking Ceremony

April 2011 – Substantial Completion June 2011 – Anticipated Final Completion December 2011 – Actual Final Completion*

Permitting Hurdles

Permitting Hurdles

12VAC5-590-190. Permits.

Construction permit issued by State Health Commissioner required prior to construction or modification of water infrastructure.

12VAC5-590-200. Procedure for obtaining a construction permit.

Requires coordination between Owner, Engineer & VA Dept of Health (VDH)

VAW’s project schedule was very ambitious with regard to start of construction & acquisition of permits.

Virginia Waterworks Regulations

Permit Coordination Meetings To assure timely acquisition of Permits, the Owner & D/B Team met with representatives of the Virginia Dept of Health (VDH) & the City of Hopewell These meetings allowed us to:

a. Present the project to the permitting agencies b. Work with them to determine pitfalls & issues c. Establish a working relationship with specific individuals within the permitting agencies (useful when permitting questions arose)

VDH Meeting: Tube Settler Issue

One potential pitfall identified by VDH related to the new tube settlers proposed for the domestic sed basin. Typically, the Department requires pilot testing to substantiate the requested design parameters. Discussion with VDH allowed VAW to provide documentation indicating similar installations with these ratings in support of the permit. Once provided, the documentation was accepted and this part of the project moved forward.

VDH Meeting: Two-Phased Permit During preliminary design phase, it was determined that substantial reductions in construction time could be achieved by obtaining the VDH permit in two phases:.

The first would be for the 2.5 MG tank whose design required minimal time, along with reduced permit review time. With the tank permit submitted, the rest of the design was completed and submitted for permit approval.

Early issuance of the tank permit allowed for its construction. Once complete, it allowed for longer plant outages that were useful during plant tie ins.

Design flexibility during construction with Design-Build: New Generator

Well into the construction of the project, it was decided to improve the standby power supply system that was currently on site.

A study was conducted to establish the size of the new generator, followed by purchase & installation of the unit.

The D/B process gave the Owner a means of adding this to the project at a competitive price.

Pilot filter testing of Industrial water resulted in the reduction of planned filters - from five to four.

Flexibility during design with Design-Build: Industrial Filter Bldg

Working with the contractor during design allowed for innovations & cost savings that would not have been possible using a “traditional” Design-Bid-Build delivery method

Examples of Cost & Schedule savings

realized using D/B

2.5 MG Domestic Clearwell: Concrete instead of steel

Domestic Filter Bldg: Auger Cast Piles

VALUE ENGINEERING OPPORTUNITY

Admin Office Building Addition: Subcontracting Non-Critical Work

Site Paving: Asphalt Reclamation

Throughout project: Steel Interior Piping

Tub Filter Bldg: Material Reclamation

Planned Treatment Plant Outages

Improvements to the domestic sedimentation basin required the plant to continue to meet customer water demands while having approximately 50% of its pre-treatment capacity off line.

All other process improvements were completed prior to initiating this outage. This included placing both the new domestic & industrial filters on-line prior to starting this work.

Project Successes

D/B approach facilitated good partnership between all parties from beginning to end.

Upgrades to operating facility fairly well coordinated with all parties

Critical tie-ins completed with minimal impact on operations.

Value added items identified throughout process, allowed for additional scope (generator).

Project completed under budget & on schedule*.

Lessons Learned

Plan the location of the Porta-Potty very carefully??

Lessons Learned

Ensure well defined scope, incl. change orders.

Better defined contingency: Change Order vs. Contingency vs. Omissions

Understand permitting constraints, requirements for permits & timeframes involved.

Coordination with 3rd parties – Security system vendor, coordination with internal functions, GC & electrical sub.