dr302-Subdrains.pdf

REPLACEMENT SCHEDULE CASE 'A'

( Pipe size in inches )

PROPOSED SUBDRAIN SIZE D 5

Coated CMP Pipe 6Existing tile size + 6''

Concrete Pipe

Existing Tile Size

> 24

Depth as required.

Backfill

Earth required

Width as

Backfill

Earth

Limits

Construction

Shoulder

Pavement

Roadway

ROW Line

Existing Tile Subdrain

Top of Backslope

Toe of Foreslope

F lo w

Shoulder

Existing Tile Subdrain Limits

Construction

ROW Line

Remove or Abandon

Temporary Easement for Subdrain

Subdrain

Existing Tile

ROW Line

Variable

L Roadway

Foreslope ROW Line

Original Ground

FLOW

Existing Tile SubdrainExisting Tile Subdrain

CASE ''A''

SECTION A-A

CASE ''A''

SECTION B-B

CASE ''B''

SECTION C-C

TYPICAL PLAN FOR REPLACING OR RELOCATING EXISTING FIELD TILE

CASE ''B'' CASE ''C''CASE ''A''

1 2 1 2

D

1 2

A

C line when possible on most direct

Replace subdrain required

Width as not reconnected but outletted by the roadway and the line is

Where tile line is severed a more parallel alignment and the line is relocated in

Where tile line is within the ROW the line is reconnected.

by the roadway and

Where the tile line is severed ditch drainage into subdrain if approved by adjacent property owners.

downstream property owners. Perforated pipe may be used to allow

Inspection access is required to allow inspection by the upstream and

A subdrain according to the replacement schedule is required.

indicates the R.O.W. limits in which replacement of tileDimension one size larger than existing line.

Replace in kind (size and type) or with 'PE' slotted pipe, a minimum of full capacity for all connected drain systems.

When multiple drains are connected to one outlet, the outlet is to provide

Contracting Authority.

Type 1 connection at no additional cost to the stronger is required, furnish and install a DR-121

When concrete culvert pipe of 2000D (Class III) or approved by the Engineer.

Cap blind ends of subdrains with a metal cap or as condition.

as to leave the existing tile drains in a functional

Connect to lines of existing tile drains in such a way cause a minimum of disturbance to existing field tile.

Install relocated or replacement subdrain so as to same size of pipe as existing line.

Replace tile lines outside the ROW limits using the inspection access at each end of replaced tile line.

the replacement schedule shown below. Install an

Replace tile lines within the ROW limits according to

Standard Subdrain Outlet shown in DR-305.

the roadway ditch, as shown in Case 'C', provide the construction requires existing subdrain to outlet into line, as shown in Case 'B'. In cases where new construction limits, relocate the tile outside the ROW more parallel to the roadway and within the right angle. Where the existing tile line alignment is relocate the tile line to accomplish a more nearly in an undesirable alignment, as shown in Case 'A', channel. Where the roadway intersects the tile line limits of the project, or outlet them in a ditch or roadway construction, replace them within the ROW

When the existing tile lines are intercepted by

104-5C

Possible Tabulation:

Subdrain Outlet

Standard Subdrain

Possible Contract Items:

Standard Specifications.

ground. Use PVC meeting the requirements of Article 4146.03 of the

4 inch diameter inspection access with cap. Minimum of 3 feet above corrugated pipe (Manning's Formula) assuming a 0.20% slope with n=0.013 for concrete pipe and n=0.025 for

Replacement sizes provide equivalent capacity based on a 6 inch settlement see DR-305.

Standard Subdrain Outlet

DR-302

REVISION

4-18-23

SHEET 1 of 1

REVISIONS: Added note 3. Renumbered notes 4-8.

APPROVED BY DESIGN METHODS ENGINEER

STANDARD ROAD PLAN

(FARM TILE REPLACEMENT)

STANDARD

SUBDRAINS

1 2 3

1 2 3 1 2 3 connection is approved by the Engineer.

A t-fitting or saddle connection is required unless an alternate

A

A

B B

A

A

C

C

BB

DOT

dr302