- ENGINEERING INFO
- CASE STUDIES
Located within Baltimore County's jurisdiction, Beachwood's cast iron water mains have been in operation for over 50 years and require upgrades to reduce maintenance costs and increase capacity. A new replacement pipeline was slated to be installed in corrosive soils in a low-lying area close to the shores of the Back River. In order to maximize the life expectancy of the line, Fusible PVC® pipe, a non-corrosive plastic pipe material, was selected in place of ductile iron for the majority of the project.
Baltimore County Public Works engineering department designed the Beachwood Water System Upgrade project to mitigate disturbance to the local community by using trenchless techniques, such as horizontal directional drilling (HDD) and pipe bursting.
The competitively bid project consisted of approximately 7,500 LF of Fusible PVC® pipe and required bidding contractors to select installation of either Fusible PVC® pipe or HDPE at bid time. Because PVC has a higher Hydrostatic Design Basis (4,000 PSI) than HDPE (1,600 PSI), PVC has a higher pressure rating for a given wall thickness, or DR. This allows use of a smaller diameter pipe when using PVC versus HDPE.
The project's flow capacity and pressure requirements called for the following pipe comparisons:
8-inch DIPS DR25 Fusible C-900® vs. 8-inch DIPS DR11 HDPE
10-inch DIPS DR25 Fusible C-900® vs. 12-inch DIPS DR11 HDPE
16-inch DIPS DR25 Fusible C-905® vs. 18-inch DIPS DR11 HDPE
A smaller diameter pipe usually results in both material and installation cost savings. All bidding contractors selected Fusible PVC® pipe in their bids.
PVC's high modulus of elasticity (400,000 psi) makes it a very strong material and allows for the use of standard ductile iron fittings for connections. This key advantage of Fusible PVC® pipe over HDPE allows contractors to make reliable, restrained-joint connections without the use of fused-on adaptors or electrofusion couplings. Since the majority of Baltimore's water system uses ductile iron fittings, it also provides Baltimore's operations group with the long-term benefits of continuing to stock standard equipment and use familiar maintenance techniques.
|Pipeline Details and Project Summary|
|Project:||Beachwood Water System Upgrades|
|Length:||2,680 LF of 16", 1,320 LF of 10",3,480 LF of 8"|
|Pipe Size:||10" DR18 & 8" DR25 Fusible C-900® & 16" DR25 Fusible C-905®|
|Installation:||Horizontal Direction Drill, Open-Cut, Pipe-bursting|
|Contractor:||Cossentiono Contracting Co.|
|HDD Contractor:||SureShot Horizontal Directional Drilling|