Drainage requirements generally dictate some type of wet retention. Not everyone wants dry retention.
Wet retention, what is it? Wet retention comes in the form of lakes and wetlands. The requirement for wetlands over a lake generally occurs when you are reconfiguring an existing wetland where it makes sense on your site plan. If you have a wet retention requirement to satisfy, then lakes are generally designated. Given the choice, I prefer lakes. They produce more fill and with littoral plantings they provide a country like setting. On the other hand, we did a lake and wetland in Davie together on a single project that created a striking backdrop and huge lot premiums. Wetland retention areas are much shallower to allow more bird life and getter water plant growth. If not done properly they can be buggy.
Money, Money, Money– Some developers use dry retention (an artificial depression of earth that is dry most of the year) because they are cheaper to build, especially if you have a fill neutral site or you will be hauling dirt off site. That can be shortsighted though and here’s why. Imagine 20 residents around a lake bounded by several species of littoral plants and fountains for special effects. The general lot premium for living on these lakes is around $40,000, that’s an $800,000 gain to sales less the cost of a lake and all the trimmings.
Further, it can elevate the cost of other dry residences without the view. We have a simple formula for lakes. Make them wide enough so the depth creates a clearer lake, plant lots of littorals around the edges early (they are very cheap) and grow into great borders, and install a recharge well to keep the lake levels high, especially if you are irrigating the grounds from the lake. Irrigating your grounds from the lake is another side benefit to this form of wet retention. If you choose to irrigate from the lake install a recharging well so the lake does not become a big mud puddle in the dry season.
Dry retention has very few benefits and some problematic conditions. I have used dry retention a few times when it is an addition to wet retention or if site plan restraints call for several dry retention areas. A dry retention area is a depression in the ground shaped like a lake (or not) that holds drainage from the grounds in wet seasons. It performs the same function as wet retention. Dry retention is very soggy and can hold water for short periods.
They can be buggy and create special problems for inexperienced lawn maintenance companies that attempt to mow these moist areas and either get stuck or create large ruts that need to be repaired. Some buyers shy away from these areas, but I have been known to get small lot premiums for bordering units. Their overall effect is positive for drainage and problems are minimal. If need be, I use them, but a lake sets a more upscale tone to the overall community.
Revisiting sites with lakes and littorals– In previous blogs you have heard me say that I occasionally revisit old projects. One of the things I look forward to are looking at how beautiful the lakes have become as the littoral plantings mature and spread around the lakeshore. At that point the ambience of the lake makes it look more natural, and wildlife abounds at these shores.
Stephen Gravett has been a real estate developer for over 45 years and was most recently CEO of Kennedy Homes for the past 11 years. He is currently full time Director of Operations for 5 Star Developers. He is a State licensed broker and since 1980 a State licensed General Contractor Unlimited. Before becoming a real estate developer, he flew B-52’s in the US Air Force during the Vietnam War.