## The Importance of Efficient Bridge Deck Drainage
Accumulation of stagnant rainwater on bridge carriageways creates severe hydroplaning hazards for motorists and drastically accelerates the penetration of moisture into deck concrete micro-cracks.
Under **MoRTH Specifications for Road and Bridge Works (5th Revision, Section 2700)**, every bridge deck must incorporate heavy-duty drainage spouts spaced at strategic intervals (typically 6m to 10m intervals along kerbs).
---
1. Anatomy of a MoRTH Compliant Drainage Spout
1. **Top Inverted Funnel / Grating Frame:** Fabricated from $10\text{ mm}$ or $12\text{ mm}$ IS 2062 MS plate with welded anti-clogging debris grating. 2. **Vertical Downspout Pipe:** Seamless or ERW pipe ($100\text{ mm}$ or $150\text{ mm}$ NB) extending at least $500\text{ mm}$ below the soffit of the bridge girder. 3. **Flange Anchors:** Continuous welded anchor perimeter for monolithic bonding into the wearing coat and deck slab. 4. **Protective Coating:** Hot-Dip Galvanized to IS 4759 with a minimum coating thickness of $85\text{ microns}$ ($610\text{ g/m}^2$) or 3-coat heavy epoxy.
