Report: DWSD Should Retire One or More Water Treatment Plants

A recent report by CH2M Hill, a national engineering firm, questions whether the City of Detroit (DWSD) should continue to operate all 5 of its existing water treatment plants (WTP) in light of major population losses and large projected capital improvement costs.

In a June 28, 2011 report, CH2M Hill begins by noting that DWSD currently operates 5 water treatment plants, which have a combined capacity of 1,640 million gallons per day (MGD).

Lake Huron . . . . . . .  400 MGD
Northeast  . . . . . . . . . 300 MGD
Water Works Park . . . 240 MGD
Springwells . . . . . . . . 540 MGD
Southwest . . . . . . . . . 160 MGD

Over the past 5 years, the Report notes, the maximum daily demand across the DWSD system has dropped from 1,050 MGD to 800 MGD.  This change in circumstances, according to CH2M Hill, raises 2 important questions:

1. Is there a different way to operate the system by reducing the number of treatment plants and thereby reducing the [capital investment] CIP requirements?
2. Are all of the transmission mains recommended in [DWSD's 50 Year] Master Plan still needed within the time frame suggested?

The CH2M Report then lays out 3 scenarios under which DWSD would retire the Southwest WTP, the Northeast WTP, or both.

CH2M Hill makes the following preliminary recommendations:

• Northeast WTP -- "retirement of the Northeast plant is the most desireable as it is the plant with the largest capital allowance to rehabilitate the plant to an acceptable level of operation."

• Southwest WTP -- "work on rehabilitation of the treatment trains at the Southwest plant should be put on hold until a detailed analysis of the system hydraulics can be completed." 

• Water Works Park WTP -- "The CIP contains an amount of $24.5M for re-working the discharge piping . . . this expenditure should be put on hold until better decisions can be made with respect to the future needs of this plant."

• Springwells WTP -- "This water treatment plant is of strategic importance to the long term operation of the DWSD transmission system. Continuing with the work related to the filter rehabilitation and pumping is important and should continue. This includes [over $442 million worth of CIP projects]."

• Transmission Mains (NOTS and Flint Loop) -- "Base on current planning projections, all of this work [$584M] should be removed from the CIP."

The CH2M Hill Report outlines a number of other recommendations (here).

Comment: The CH2M Hill Report appears to have been published during the time period in which DWSD was evaluating the CIP, between early May and late July. It is unclear, however, whether the report was part of the decision making process. It was distributed only yesterday to attendees of a TAC Meeting.  

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