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NEORSD Expects to Finish DST By December 2019

Launched in 2011, ProjectClean Lake is a $3 billion, 25-yearplan to reduce CSO volumesaffecting Lake Erie via the con-struction of seven storage tunnels,green infrastructure and three treat-ment plant improvements that willreduce CSO by four billion gallonsannually.“When Cleveland entered into

its consent decree in 2011, [thecity] discharged an estimated 4.5billion gallons of raw sewage intothe lake,” noted Salini Impregilo.“Although the volume is half ofwhat it was in the 1970s, the cityneeds to reduce it even more tomeet standards set under the CleanWater Act.”“The Dugway series of sewer

projects is extensive and critical tothe future of clean water in theregion” Elting said. “It is a networkof sewers and tunnels being con-structed to reduce combinedCSOs, ensuring a cleaner environ-ment for the Glenville neighbor-hood and beyond.”The Dugway work will create

32,000 ft. of new sewers rangingfrom three to 24 ft. in diameter.Dugway West was completed inAugust 2017 ($52 million) andDugway South was substantiallycompleted in August 2018 ($26million). The Dugway EastInterceptor Relief Sewer project($11 million, completed inDecember 2011) also helps to mit-igate combined sewer overflowson Cleveland’s east side, but thisproject was completed prior toProject Clean Lake.The Dugway tunnels, along

with the Euclid Creek Tunnel proj-ects (completed in 2015), will han-dle 950 million gallons annually.And the new tunnels are needed.“Cleveland’s earliest sewers are

combined sewers,” stated a docu-ment distributed to local residentsduring public consultations. “Builtaround the turn of the 19th century,these sewers carry sewage andstormwater in a single pipe. Duringheavy rains, when there is a dra-matic increase of water flowingthrough the sewers, some of thecombined wastewater andstormwater is allowed to overflowinto area waterways to preventurban flooding. This combinedCSO harms our environment.”Design work for the DST was

completed by a joint venture ofMWH Americas Inc. and MottMacDonald LLC.A design-bid-build contract was

selected based on a combination ofthe NEORSD’s governing rulesand the many geotechnical, proper-ty acquisition, flow monitoring,property and hydraulic work asso-ciated with the project.“Meeting our consent decree

dates, CSO requirements, andavoiding the large claims by iden-tifying and investigating all of themajor risk items were among thetop challenges,” said theNEORSD’s Doug Lopata. “Via theEuclid Creek Tunnel project, welearned the importance of identify-ing utilities early on for either relo-cation or avoidance when possible.”The lifespan of the tunnel is

approximately 100 years. The ini-tial boring had the DST at 27 ft. indiameter, but once the precast seg-

mental concrete rings lined thewalls, the internal diameter is closeto 24 ft. The tunnel is between 200to 230 ft. below ground and has sixshafts of varying diameters anddepths, along with a series of con-crete structures for the collectionand transporting of wastewater andrainwater.Thus far, the Salini

Impregilo/Lane Construction JVhas completed the tunnel, six shafts— DST-1, DST-2, DST-4, DST-5.DST-7, and DST-8 — and fouradits at DST-2, DST-4, DST-5, andDST-7. The remaining workincludes lining the 200 ft. of theECT tail tunnel, which covers thearea from the DST-1 shaft to theECT tail tunnel. Crews are current-ly prepping the work site."The lining will be cast-in-place

and should be completed inOctober,” explained Buck Depew,the NEORSD’s construction

Northeast Ohio Regional Sewer District photoThe TBM before mining, being

brought to the mining tunnel shaft.

Northeast Ohio Regional Sewer District photoAssembly of the Dugway Storage Tunnel project’s gantry crane.

TUNNEL from page 1

see TUNNEL page 32Northeast Ohio Regional Sewer District photo

The TBM’s cutterhead in place in the mining shaft.

“Meeting our consent decree dates, CSO requirements, and avoidingthe large claims by identifying and investigating all of the major riskitems were among the top challenges.”

Doug LopataNortheast Ohio Regional Sewer District