1240815MAINTENANCE MANUAL rcd 3 12 2026

4. GUTTERS/DOWNSPOUTS/SPLASH PADS—Under state and local stormwater regulations, runoff water flowing off of roofs is considered “clean” and does not necessarily have to be directed to the detention system which maybe basins, ponds, drywells, underground pipes and so forth. In general, allowing the water to flow through areas of dense vegetation (woodlands, meadows, and so forth, but not basic lawn areas) is sufficient to clean the water even further. In order for the water to flow clean, the system should be maintain clean. 5. DRYWELLS- In general these are large concrete cylinders (similar to concrete manholes) with numerous openings in the side walls and open bottoms. The concrete cylinders are placed below ground and are almost always surrounded by several feet of clean crushed stone beneath the cylinder and along its side walls. A plastic type filter cloth (called a “geotextiles” is placed between the stone and the surrounding soil to keep soil particles from getting into the spaces between the stones. Runoff water is piped to the drywells where it first slows into the concrete cylinders. If the inflow of water is large enough, the openings in the stone will fill with water and the cylinder will fill with water. This rising water will pass through the openings in the cylinder grove walls into the surrounding stone. If the inflow is sufficiently large the concrete cylinder may fill to the top and spill out through an overflow pipe or bubble out through a grate covering the top of the cylinder. 17