Gutter Downspout CVollector Pipe?

[DD716TED]

I have built a new carport and need to connect the gutter to the existing 6" PVC house gutter storm drain system. Directly beneath where the new downspout is to be installed but 18" underground is the existing drain line. I have dug down to the line but can't remove enough dirt to cut / install a "T". The pipe is not a smooth surface white PVC but is white with small ripples on it. IT IS NOT BLACK plastic DRAIN LINE.. How do I tap into this line? attached picture shows what I am attempting to do.. Need ideas.

[HayZee518]

why not a roll up downspout and let the water run away from the structure. the water will leach into the ground and may, somehowleach into the drain pipe

[DD716TED]

Good Idea BUT..

Home Owners Association require all downspouts be plumbed into storm drain... Thanks